How to calculate the area and perimeter of a triangle?

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For a general triangle: [img] https:///wp-content/uploads/2016/03/altalanos.png [/ img] For an isosceles triangle: [img] https:///wp- content / uploads / 2016/03 / equator.png [/ img] For an equilateral triangle: [img] https:///wp-content/uploads/2016/03/equalold.png [/ img] For a right triangle: [img] https:///wp-content/uploads/2016/03/derekszogu.png [/ img]  
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Sides of a triangle are in the ratio of 12 : 17 : 25 and its perimeter is 540 cm. Find its area. -Maths 9th

Description : Sides of a triangle are in the ratio of 12 : 17 : 25 and its perimeter is 540 cm. Find its area. -Maths 9th

Last Answer : Let the sides of the triangle be a = 12x cm, b = 17x cm, c = 25x cm Perimeter of the triangle = 540 cm Now, 12x + 17x + 25x = 540 ⇒ 54x = 54 ⇒ x = 10 ∴ a = (12 x10)cm = 120cm, b = (17 x 10) cm = 170 cm and c = (25 x 10)cm = 250 cm Now, semi-perimeter, s = 5402cm = 270 cm

Find the area of a triangle having perimeter 32cm. One side of its side is equal to 11cm and difference of the other two is 5cm. -Maths 9th

Description : Find the area of a triangle having perimeter 32cm. One side of its side is equal to 11cm and difference of the other two is 5cm. -Maths 9th

Last Answer : Solutions :- We have, Perimeter of triangle = 32 cm One of its side = 11 cm Let the second side be x And third side be x + 5 Perimeter of triangle = sum of three sides A/q => 11 + x + x + 5 ... 13 cm Now, By using heron's formula, Find the area of a triangle :- Answer : Area of triangle = 43.81 cm²

Find the area of a triangle whose sides are 4.5 cm and 10 cm and perimeter 10.5 cm. -Maths 9th

Description : Find the area of a triangle whose sides are 4.5 cm and 10 cm and perimeter 10.5 cm. -Maths 9th

Last Answer : Step-by-step explanation: ◾As we have given the two sides of triangle, let the three sides of triangle are (a) , (b), (c) . ◾And perimeter of given triangle is 10.5 cm ◾were, let us assume the sides are, ... . ◾So, the area of a triangle whose sides are 4.5 cm and 10 cm and perimeter 10.5 [Area ]=

If the perimeter of an equilateral triangle is 24cm, then find the area of the triangle -Maths 9th

Description : If the perimeter of an equilateral triangle is 24cm, then find the area of the triangle -Maths 9th

Last Answer : Perimeter of equilateral triangle = 24cm ( there are three equal sides in an e quilateral triangle ) Each side = 24 / 3 = 8cm Area of an equilateral triangle = root 3 / 4 s square = root 3 / 4 × 8 square = root 3 / 4 x 64 = root 3 × 16 = 16 root 3

If the perimeter of an equilateral triangle is 24cm, then find the area of the triangle -Maths 9th

Description : If the perimeter of an equilateral triangle is 24cm, then find the area of the triangle -Maths 9th

Last Answer : Perimeter of equilateral triangle = 24cm ( there are three equal sides in an e quilateral triangle ) Each side = 24 / 3 = 8cm Area of an equilateral triangle = root 3 / 4 s square = root 3 / 4 × 8 square = root 3 / 4 x 64 = root 3 × 16 = 16 root 3

The perimeter of an equilateral triangle is 60 m. The area is -Maths 9th

Description : The perimeter of an equilateral triangle is 60 m. The area is -Maths 9th

Last Answer : Let each side of an equilateral be x. Then, perimeter of an equilateral triangle = 60 m x + x + x = 60 ⇒ 3x = 60 ⇒ x = 60/3 = 20 m Area of an equilateral triangle = √3/4 (Side)2 = (√3/4) x 20 x 20 = 100 √3 m2 Thus, the area of triangle is 100√3 m2.

The perimeter of an equilateral triangle is 60 m. The area is -Maths 9th

Description : The perimeter of an equilateral triangle is 60 m. The area is -Maths 9th

Last Answer : (d) Let each side of an equilateral be x. Then, perimeter of an equilateral triangle = 60 m x + x + x = 60 ⇒ 3x = 60 ⇒ x = 60/3 = 20 m Area of an equilateral triangle = √3/4 (Side)2 = (√3/4) x 20 x 20 = 100 √3 m2 Thus, the area of triangle is 100√3 m2.

The base of an isosceles triangle is 24cm and its area is 192cm^2. Find its perimeter -Maths 9th

Description : The base of an isosceles triangle is 24cm and its area is 192cm^2. Find its perimeter -Maths 9th

Last Answer : Given, base of an isosceles triangle =24 cm Area of isosceles triangle =192 sq.cm Area = 21​×b×h ∴192=224.h​ ∴h=16 cm Side=h2+122​=256+144​=20 cm Perimeter of triangle =2a+b =2(20)+24=64 cm

The area of a square and circle is same and the perimeter of square and equilateral triangle is same, -Maths 9th

Description : The area of a square and circle is same and the perimeter of square and equilateral triangle is same, -Maths 9th

Last Answer : (b) 9 : 4√3.Let each side of the square = a cm. Then, Area of square = a2 cm2 Also, let r be the radius of the circle. Then, πr2 = a2 Let each side of the equilateral triangle = b cm. Then 3b = 4a ⇒ ... ratio between area of circle and area of equilateral Δ is a2 : \(rac{4\sqrt3a^2}{9}\) = 9 : 4√3.

Each side of an equilateral triand 12 is \( 24 cm \) the mid - point of its sides are joined to form another tranpla this brress is doins centinuously infinite46. The perimeter of 7 th triangle is \( ( \) in \( cm ) \)a) \( \frac{3}{4} \)b) \( \frac{5}{8} \)c) \( \frac{9}{8} \)d) \( \frac{7}{8} \)47. The sum of perimeter of all triangle is (in \( cm \) )a) 144b) 625c) 400d) 16948. The area of all the triangle is (in sq cm)a) 576b) \( 144 \sqrt{3} \)c) \( 169 \sqrt{3} \)d) \( 192 \sqrt{3} \)49. The sum of perimeter of first 6 triangle is (in \( cm \) )a) 120b) \( \frac{567}{4} \)c) \( \frac{569}{4} \)d) 14450. The side of the 5th triangle is (in \( cm \) )a) 6b) \( 1.5 \)c) \( 0.75 \)d) 3

Description : Each side of an equilateral triand 12 is \( 24 cm \) the mid - point of its sides are joined to form another tranpla this brress is doins centinuously infinite46. The perimeter of 7 th triangle is \( ( \) in \( cm ) \)a) \( \ ... of the 5th triangle is (in \( cm \) )a) 6b) \( 1.5 \)c) \( 0.75 \)d) 3

Last Answer : Each side of an equilateral triand 12 is \( 24 cm \) the mid - point of its sides are joined to form another tranpla ... ( 1.5 \) c) \( 0.75 \) d) 3

What is the area and perimeter of a scalene triangle when angle 75 degrees is opposite to side 25cm with another angle of 42 degrees?

Description : What is the area and perimeter of a scalene triangle when angle 75 degrees is opposite to side 25cm with another angle of 42 degrees?

Last Answer : Using the sine rule in trigonometry its area is 192.885 squarecm and its perimeter is 65.379 cm both rounded to three decimalplaces.

What is the perimeter and area of a triangle whose longest side is 162cm when two of its angles are 37.25 degrees and 48.4 degrees?

Description : What is the perimeter and area of a triangle whose longest side is 162cm when two of its angles are 37.25 degrees and 48.4 degrees?

Last Answer : Using the sine rule in trigonometry the perimeter of thetriangle is 381.83 cm and its area is 5956.67 square cm bothrounded to two decimal places

What is the perimeter of a triangle that has a area of 6.5 cm?

Description : What is the perimeter of a triangle that has a area of 6.5 cm?

Last Answer : The minimum perimeter is when the triangle is an equilateraltriangle. The perimeter of any other triangle with the same areawill be longer.In the case of an equilateral triangle area = (√3)/4 side²→ side = ... /√3) ≈ 11.62 cm→ The triangle has a perimeter greater than or equal to approx11.62 cm.

What is the perimeter and area of an equilateral triangle with a side of 8?

Description : What is the perimeter and area of an equilateral triangle with a side of 8?

Last Answer : Perimeter of equilateral triangle: 24 units Area of equilateral triangle: 27.713 square units rounded to three decimal places

Calculate the perimeter of a rectangle whose area is 25x2 – 35x + 12. -Maths 9th

Description : Calculate the perimeter of a rectangle whose area is 25x2 – 35x + 12. -Maths 9th

Last Answer : Given, Area of rectangle = 25x2 - 35x + 12 We know, area of rectangle = length breadth So, by factoring 25x2 - 35x + 12, the length and breadth can be obtained. 25x2 - 35x + 12 = 25x2 - 15x - 20x + 12 => 25x2 - 35x + ... )] = 2(5x - 3 + 5x - 4) = 2(10x - 7) = 20x - 14 So, the perimeter = 20x - 14

Write a shell script to accept length and breadth of rectangle from user. Calculate and display area, perimeter, of entered values using choice entered by user.

Description : Write a shell script to accept length and breadth of rectangle from user. Calculate and display area, perimeter, of entered values using choice entered by user.

Last Answer : #!/bin/bash # GNU bash, version 4.3.46 echo "Enter Length of Rectangle: " read length echo "Enter Breadth of Rectangle: " read breadth echo "Which operation you want to perform? 1: area 2: perimeter" read ... ) res=` echo 2 \* $length \* $breadth | bc` ;; esac echo "Result is $res" exit 0

The sides of a triangle are in the ratio of 3 : 4 : 5 and its perimeter is 510 m. What is the measure of its greatest side? -Maths 9th

Description : The sides of a triangle are in the ratio of 3 : 4 : 5 and its perimeter is 510 m. What is the measure of its greatest side? -Maths 9th

Last Answer : Let the sides of triangle be 3x,4x,5x Perimeter =3x + 4x + 5x=144 cm 12x=144 ∴x=12 Then sides of triangle are 3x=3 12=36 cm, 4x=4 12=48 cm, 5x=5 12=60 cm. Now, Semi perimeter, s=2 Sum of sides of ... , Area of triangle =s (s−a)(s−b)(s−c) = 72(72−36)(72−48)(72−60) = 72 36 24 12 = 864 cm2

The perimeter of a right triangle is 30 cm. If its hypotenuse is 13 cm, then what are two sides? -Maths 9th

Description : The perimeter of a right triangle is 30 cm. If its hypotenuse is 13 cm, then what are two sides? -Maths 9th

Last Answer : The other two sides of the triangle are 12 cm and 5 cm Explanation: Let the other two sides of triangle be x and y It's hypotenuse is 13 cm Perimeter of triangle = Sum of all sides ... When y = 12 x=17-y = 17-12 =5 So, the other two sides of the triangle are 12 cm and 5 cm

If the lengths of the sides of a triangle are in the ratio 6:11:15 and it's perimeter is 96cm , then the height corresponding to the longest side is -Maths 9th

Description : If the lengths of the sides of a triangle are in the ratio 6:11:15 and it's perimeter is 96cm , then the height corresponding to the longest side is -Maths 9th

Last Answer : LET EACH SIDE BE X 6X+11X+15X=96 32X=96 X=3 SIDES=6 3=18 11 3=33 15 3=45 AREA OF TRIANGLE BY HERONS FORMULA=S=96/2=48 WHOLE UNDERROOT 48 48-18 48-33 48-45 UNDERROOT=12 4 30 15 3 4 3 15ROOT2 180 ... bh/2 180root2=18 h/2 360root2=18h h=20 root2 But root 2=1.4(approx) h=20 1.4(approx) h=28cm(approx).

If the lengths of the sides of a triangle are in the ratio 6:11:15 and it's perimeter is 96cm , then the height corresponding to the longest side is -Maths 9th

Description : If the lengths of the sides of a triangle are in the ratio 6:11:15 and it's perimeter is 96cm , then the height corresponding to the longest side is -Maths 9th

Last Answer : LET EACH SIDE BE X 6X+11X+15X=96 32X=96 X=3 SIDES=6 3=18 11 3=33 15 3=45 AREA OF TRIANGLE BY HERONS FORMULA=S=96/2=48 WHOLE UNDERROOT 48 48-18 48-33 48-45 UNDERROOT=12 4 30 15 3 4 3 15ROOT2 180 ... bh/2 180root2=18 h/2 360root2=18h h=20 root2 But root 2=1.4(approx) h=20 1.4(approx) h=28cm(approx).

The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. -Maths 9th

Description : The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. -Maths 9th

Last Answer : Area of the triangle =

The perimeter of a triangle is 50 cm. One side of a triangle is 4 cm longer than the smaller side and the third side is 6 cm less than twice the smaller side. -Maths 9th

Description : The perimeter of a triangle is 50 cm. One side of a triangle is 4 cm longer than the smaller side and the third side is 6 cm less than twice the smaller side. -Maths 9th

Last Answer : Let the smallest side of the triangle be x cm long So, second side =(x+4)cm and third side =(2x−6)cm Given, perimeter =50cm Therefore, x+(x+4)+(2x−6)=50 ⇒4x=52 ⇒x=13cm So, first side of the triangle is ... =25cm Therefore, area of Δ=s(s−a)(s−b)(s−c) =25(25−13)(25−17)(25−20) =25 12 8 5 = 2030 cm2

The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. -Maths 9th

Description : The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. -Maths 9th

Last Answer : Area of the triangle =

The perimeter of a triangle is 50 cm. One side of a triangle is 4 cm longer than the smaller side and the third side is 6 cm less than twice the smaller side. -Maths 9th

Description : The perimeter of a triangle is 50 cm. One side of a triangle is 4 cm longer than the smaller side and the third side is 6 cm less than twice the smaller side. -Maths 9th

Last Answer : According to question find the area of triangle.

The perimeter of an isosceles triangle is 32 cm. -Maths 9th

Description : The perimeter of an isosceles triangle is 32 cm. -Maths 9th

Last Answer : Let each of the equal side of isosceles triangle = 3x cm and base of isosceles triangle = 2x cm ∴ Perimeter = 3x + 3x + 2x 32 = 8x ⇒ x = 4 ∴ Sides are 3 x 4,3 x 4, 2 x 4 i.e., 12 cm, 12 cm, 8 cm Now, ... c)) = under root(√16(16 - 12)(16 - 12)(16 - 8)) = under root (√16 x 4 x 4 x 8) = 32√2 cm2

The perimeter of a triangle is 50 cm. -Maths 9th

Description : The perimeter of a triangle is 50 cm. -Maths 9th

Last Answer : Let the length of the smallest side = x According to the statement, other two sides of the triangle will be x + 4 and 2x - 6 Perimeter of triangle = x + x + 4 + 2x - 6 ⇒ 50 = 4x - 2 ⇒ 4x = 52 ⇒ x = 13 ∴ Sides of ... ) = root under( √5 x 5 x 3 x 4 x 4 x 2 x 5) = 20 √30 = 20 x 5.48 = 109.6 cm2

The perimeter of an isosceles triangle is 15 cm -Maths 9th

Description : The perimeter of an isosceles triangle is 15 cm -Maths 9th

Last Answer : Yes, 2b + a = 15 ⇒ 25 + 7 = 15 ⇒ b = 14 ∴ Area of isosceles triangle = 7/4 root under( √4b2 - a2) = 7/4 root under( √4 x 42 - 72) = 7/4 root under( √64 - 49) = 7/4. √15 cm2 Curiosity, knowledge, truthfulness.

A point within an equilateral triangle whose perimeter is 30 m is 2 m from one side and 3 m from another side. Find its distance from third side. -Maths 9th

Description : A point within an equilateral triangle whose perimeter is 30 m is 2 m from one side and 3 m from another side. Find its distance from third side. -Maths 9th

Last Answer : answer:

What is the perimeter of the triangle with the vertices A(–4, 2), B(0, –1) and C(3, 3) ? -Maths 9th

Description : What is the perimeter of the triangle with the vertices A(–4, 2), B(0, –1) and C(3, 3) ? -Maths 9th

Last Answer : The two given lines are ax + by + c1 = 0 and ax + by + c2 = 0. Any line parallel to these two lines and midway between them is ax + by + c = 0 ...(i) Putting x = 0, y = \(-rac{c}{b}\) is ... c1 = c - c2 ⇒ c = \(rac{c_1+c_2}{2}\)∴ Required equation is ax + by + \(rac{c_1+c_2}{2}\) = 0.

A square and an equilateral triangle each have a perimeter of 72 cm. How much longer is one side of the triangle than one side of the square?

Description : A square and an equilateral triangle each have a perimeter of 72 cm. How much longer is one side of the triangle than one side of the square?

Last Answer : You see you can do is 72cm divide by 3 because an equilateral triangle has 3 sides 72cm/3 = 24cm(I am not sure if this is right)

what- Suppose the side lengths of a triangle have the ratio 5:12:13. Some possible triangles are shown here. Now suppose the perimeter of the triangle is ninety centimeters.What are the side lengths?

Description : what- Suppose the side lengths of a triangle have the ratio 5:12:13. Some possible triangles are shown here. Now suppose the perimeter of the triangle is ninety centimeters.What are the side lengths?

Last Answer : What is the triangle

what- The perimeter of the triangle shown is 120 inches. Find the length of the longest side?

Description : what- The perimeter of the triangle shown is 120 inches. Find the length of the longest side?

Last Answer : 50 in

what- Triangle TUV has a perimeter of 52 cm.Which angle has the greatest measure?

Description : what- Triangle TUV has a perimeter of 52 cm.Which angle has the greatest measure?

Last Answer : T

Perimeter of a right triangle = ?

Description : Perimeter of a right triangle = ?

Last Answer : : Perimeter of a right triangle = land + height + hypotenuse)

What is the perimeter of triangle if its longest side is 162cm when two of its angles are 37.25 degrees and 48.4 degrees?

Description : What is the perimeter of triangle if its longest side is 162cm when two of its angles are 37.25 degrees and 48.4 degrees?

Last Answer : The largest angle then will be 94.35 degrees opposite the longest sides of 162cm and by using the sine rule of 120/sin(94.35) = b/sinB = c/sinC the perimeter of the triangle works out as 381.83cm rounded to two decimal places.

What is the perimeter and height of a triangle that has a base length of 15cm with base angles of 28.67 degrees and 15.5 degrees?

Description : What is the perimeter and height of a triangle that has a base length of 15cm with base angles of 28.67 degrees and 15.5 degrees?

Last Answer : Using the sine formulae of a/A=b/B=c/C and A/a=B/b=C/c intrigonometry the perimeter of the triangle is 31.08 cm with aheight of 2.76 cm both rounded to two decimal places.

what is the perimeter of the triangle ABC with point A(-3,2), B(4,4), C(1,-2)?

Description : what is the perimeter of the triangle ABC with point A(-3,2), B(4,4), C(1,-2)?

Last Answer : I need help

Each of the equal sides of an isosceles triangle is 5 cm greater than the base. The perimeter is 46 Centimeters. What is the length of each side of the triangle?

Description : Each of the equal sides of an isosceles triangle is 5 cm greater than the base. The perimeter is 46 Centimeters. What is the length of each side of the triangle?

Last Answer : a is one of the equal sides of the iscosceles triangle b is the base perimeter is a + a + b = 46cm a = b + 5cm subsitute a for b + 5cm in the perimeter equation b + 5cm + b + 5cm + b = 46cm ... = 12cm + 5cm a = 17cm So you have 2 sided with the length of 17cm and the base with the length of 12cm

Each of the equal sides of an isosceles triangle is 5 cm greater than the base. The perimeter is 46 Centimeters. What is the length of each side of the triangle?

Description : Each of the equal sides of an isosceles triangle is 5 cm greater than the base. The perimeter is 46 Centimeters. What is the length of each side of the triangle?

Last Answer : a is one of the equal sides of the iscosceles triangle b is the base perimeter is a + a + b = 46cm a = b + 5cm subsitute a for b + 5cm in the perimeter equation b + 5cm + b + 5cm + b = 46cm ... = 12cm + 5cm a = 17cm So you have 2 sided with the length of 17cm and the base with the length of 12cm

The perimeter of a triangle with vertices (0, 4), (0, 0) and (3, 0) is: (a) 12 units (b) 11 units (c) 5units (d) (7 + √5)units

Description : The perimeter of a triangle with vertices (0, 4), (0, 0) and (3, 0) is: (a) 12 units (b) 11 units (c) 5units (d) (7 + √5)units

Last Answer : (a) 12 units

The sides of a triangle are in the ratio 3 : 5 : 7 and its perimeter is 30 cm. The length of the greatest side of the triangle in cm is (1) 6 (2) 10 (3) 14 (4) 16

Description : The sides of a triangle are in the ratio 3 : 5 : 7 and its perimeter is 30 cm. The length of the greatest side of the triangle in cm is (1) 6 (2) 10 (3) 14 (4) 16

Last Answer : (3) 14

An equilateral triangle has a side of length 4.68m. What it is perimeter ?

Description : An equilateral triangle has a side of length 4.68m. What it is perimeter ?

Last Answer : Since each side is equal, just multiply by 3.

The sides of a triangle are in the ratio of 1/2:1/3:1/4. If its perimeter is 52 cm, the length of the smallest side is : (A) 9 cm (B) 10 cm (C) 11 cm (D) 12 cm

Description : The sides of a triangle are in the ratio of 1/2:1/3:1/4. If its perimeter is 52 cm, the length of the smallest side is : (A) 9 cm (B) 10 cm (C) 11 cm (D) 12 cm

Last Answer : (D) 12 cm Answer: D Explanation: Sides of a triangle are in the ratio of a:b:c = 1/2:1/3:1/4 = 12 /2 : 12 /3 : 12 /4 = 6:4:3 Let the lengths of three sides of the triangle be 6x, 4x, 3x Perimeter of the ... ⇒ 52 cm = 6x + 4x + 3x x = 52/13 = 4 cm length of the smallest side = 3x = 3 x 4 = 12 cm

How do i calculate the metres of perimeter for a rectangle with sides 17.5 m by 6.25 m wide?

Description : How do i calculate the metres of perimeter for a rectangle with sides 17.5 m by 6.25 m wide?

Last Answer : Need answer

How do i calculate the metres of perimeter for a rectangle with sides 17.5 m long by 3.3 m wide?

Description : How do i calculate the metres of perimeter for a rectangle with sides 17.5 m long by 3.3 m wide?

Last Answer : Perimeter of rectangle: 17.5+3.3+17.5+3.3 = 41.6 metres

How do i Calculate the metres of perimeter of a square with sides 2.750 m long?

Description : How do i Calculate the metres of perimeter of a square with sides 2.750 m long?

Last Answer : multiply by 2.75m by 4

Activities to teach perimeter and area?

Description : Activities to teach perimeter and area?

Last Answer : Quick google search turned up these: http://www.proteacher.org/c/321_Area_and_perimeter.html http://www.teach-nology.com/worksheets/math/area/ http://findarticles.com/p/articles/mi_qa3666/is_199905/ai_n8850924 http://www.superteacherworksheets.com/geometry.html There’s a lot out there.

Perimeter of the rhombus is 100 m and its diagonal is 40m. Find the area of rhombus. -Maths 9th

Description : Perimeter of the rhombus is 100 m and its diagonal is 40m. Find the area of rhombus. -Maths 9th

Last Answer : Perimeter of rhombus =4 side ⇒ 100=4 side ⇒ side= 4 100 ⇒ side=25 We know diagonals of a rhombus divides the rhombus in two equilateral triangle. Now, we are going to find area of 1 equilateral triangle. Semi perimeter = ... ) = 45 5 20 20 = 90000 =300m 2 ⇒ Area of rhombus =2 300m 2 =600m 2

The perimeter of one face of a cube is 20 cm. Find the lateral surface area of the cube. -Maths 9th

Description : The perimeter of one face of a cube is 20 cm. Find the lateral surface area of the cube. -Maths 9th

Last Answer : Let a be the edge of cube, ∴ Perimeter of one face of cube = 20 cm ⇒ 4a = 20 ⇒ a = 5 ∴ Lateral surface area of cube = 4a2 = 4 (5)2 = 100 cm2

The perimeter of one face of a cube is 20 cm. Find the lateral surface area of the cube. -Maths 9th

Description : The perimeter of one face of a cube is 20 cm. Find the lateral surface area of the cube. -Maths 9th

Last Answer : Let a be the edge of cube, ∴ Perimeter of one face of cube = 20 cm ⇒ 4a = 20 ⇒ a = 5 ∴ Lateral surface area of cube = 4a2 = 4 (5)2 = 100 cm2