What is the point of contact when the tangent line y equals x plus c touches the circle x squared plus y squared equals 4?

1 Answer

Answer :

The line meets the circle when:y = x + c→ x² + y² = 4→ x² + (x + c)² - 4 = 0→ x² + x² +2cx + c² - 4 = 0→ 2x² + 2cx + (c² - 4) = 0If the line is a tangent to the circle, this has a repeatedroot. This occurs when the discriminant is 0, ie when:(2c)² - 4 × 2 × (c² - 4) = 0→ 4c² - 8c² + 32 = 0→ 4c² = 32→ c² = 8→ c = √8 = 2√2This can now be substituted back into the meeting equationabove:2x² + 2cx + (c² - 4) = 0→ 2x² + 2 × 2√2 × x + (√8)² - 4 = 0→ 2x² + 4√2 x + 8 - 4 = 0→ x² + 2√2 x + 2 = 0→ (x + √2)² = 0→ x = -√2→ y = x + 2√2= -√2 + 2√2= √2→ point of contact is (-√2, √2)

Related questions

Description : What are the values of x y and k when the line y equals 3x plus 1 is a tangent to the circle x squared plus y squared equals k?

Last Answer : If y = 3x + 1 is a tangent to x² + y² = k (k > 0 since it isa square), then where they meet has a repeated root; they meetat:x² + (3x + 1)² = k→ x² + 9x² + 6x + 1 - k = 0→ 10x² + 6x + (1 - k) = 0This is the ... 3/10→ y = 3 -3/10 + 1 = 9/10 + 1 = 1/10→ point of contact is (-3/10, 1/10) with k = 1/10

Description : What is the length of a tangent line from the point 7 -2 to a point when it touches the circle x2 plus y2 -10 equals 49?

Last Answer : x² + y² - 10 = 49→ x² + y² = 59= (x - 0)² + (y - 0)² = (√59)²→ circle has centre (0, 0) - the origin - and radius √59The point (7, -2) has a distance from the centre of the circleof:√((7 - 0)² + (-2 - 0)²) = √(7² + (-2)²) = √(49 + 4) = √53

Description : What is the value of y when y equals 2x plus 1.25 is a tangent to the curve y squared equals 10x?

Last Answer : If the line y = 2x+1.25 is a tangent to the curve y^2 = 10x thenit works out that when x = 5/8 then y = 5/2

Description : What is the distance from a point on the x axis to the centre of a circle when a tangent line at the point 3 4 meets the circle of x2 plus y2 -2x -6y plus 5 equals 0?

Last Answer : Circle equation: x^2 +y^2 -2x -6y +5 = 0Completing the squares: (x-1)^2 +(y-3)^2 = 5Centre of circle: (1, 3)Tangent line meets the x-axis at: (0, 5)Distance from (0, 5) to (1, 3) = 5 units using the distanceformula

Description : What is the length of the tangent line from the point 9 0 to the circle x2 plus 8x plus y2 -9 equals 0?

Last Answer : Equation of circle: x^2 +8x +y^2 -9 = 0Completing the square: (x+4)^2 +y^2 = 25Radius of circle: 5Center of circle: (-4, 0)Distance from (9, 0) to (-4, 0) = 13 which is ... the length of the tangent line is 12 unitsNote that the tangent line of a circle meets the radius of thecircle at right angles

Description : What is the tangent line equation of the circle 2x2 plus 2y2 -8x -5y -1 equals 0 at the point 1 -1 on its circumference?

Last Answer : Circle equation: 2x^2 +2y^2 -8x -5y -1 = 0Divide all terms by 2: x^2 +y^2 -4x -2.5y -0.5 = 0Completing the squares: (x-2)^2 +(y-1.25)^2 = 6.0625Center of circle: (2, 1.25)Point of contact: (1 ... 9Tangent equation: y--1 = -4/9(x-1) => 9y = -4x -5Tangent line equation in its general form: 4x+9y+5 = 0

Description : What is the equation of the tangent line that meets the circle x2 -4x plus y2 -6y equals 4 at the point 6 4?

Last Answer : Circle equation: x^2 -4x +y^2 -6y = 4Completing the squares: (x-2)^2 +(y-3)^2 = 17Point of contact: (6, 4)Center of circle: (2, 3)Slope of radius: 1/4Slope of tangent line: -4Tangent equation: y-4 = -4(x-6) => y = -4x+28Tangent line equation in its general form: 4x+y-28 = 0

Description : What is the length of the tangent line from the point 8 2 to a point where it meets the circle x2 plus y2 -4x -8y -5 equals 0?

Last Answer : Equation of circle: x^2 +y^2 -4x -8y -5 = 0Completing the squares: (x-2)^2 +(y-4)^2 = 25 which is radiussquaredCenter of circle: (2, 4)Tangent line originates from: (8, ... angle triangleUsing Pythagoras theorem: distance^2 minus radius^2 = 15Therefore length of tangent line is the square root of 15

Description : What is the point of contact between the line y equals x plus 4 and the circle x2 plus y2 -8x plus 4y equals 30?

Last Answer : Equations: y = x+4 and x^2 +y^2 -8x +4y = 30It appears that the given line is a tangent line to the givencircle and the point of contact works out as (-1, 3)

Description : What is the solution when y equals 2x plus 1 is a tangent to the circle 5y2 plus 5x2 equals 1?

Last Answer : If y = 2x+1 is a tangent line to the circle 5y^2 +5x^2 = 1 thenthe point of contact is at (-2/5, 1/5) because it has equalroots

Description : What is the point of contact when the line y equals 2x meets the circle x2 plus y2 -8x -y plus 5 equals 0?

Last Answer : If: y = 2xThen: y^2 = 4x^2If: x^2 +y^2 -8x -y +5 = 0Then: x^2 +4x^2 -8x -2x +5 = 0Transposing terms: 5x^2 -10x +5 = 0Dividing all terms by 5: x^2 -2x +1 = 0Factorizing the above: (x-1)(x-1) = 0 meaning x = 1By substitution into original equations point of contact is madeat: (1, 2)

Description : If `16l^2+9m^2=24lm+6l+8m+1` and the line `mx+ly=1` is tangent to circle `S_1=0` then the equation of circle `S_2=0` which touches `S_1=0` at `(0,0)`

Last Answer : If `16l^2+9m^2=24lm+6l+8m+1` and the line `mx+ly=1` is tangent to circle `S_1=0` then the equation of ... `3x^(2)+3y^(2)-8x-6y=0` D. none of theese

Description : What are the points of contact when the line x -y equals 2 crosses the curve x squared -4y squared equals 5 showing work?

Last Answer : If: x -y = 2 then x^2 = (2+y)^2 => 4+4y+y^2If: x^2 -4y^2 = 5 then x^2 = 5+4y^2So: 5+4y^2 = 4+4y+y^2Transposing terms: 3y^2 -4y +1 = 0Factorizing the above: (3y-1)(y-1) = 0 meaning y = 1/3 or y =1By substitution contacts are made at: (7/3, 1/3) and (3, 1)

Description : What are the points of intersection of the line 2x plus 5y equals 4 with the curve y squared equals x plus 4?

Last Answer : If: 2x +5y = 4 then 25y^2 = 4x^2 -16x +16If: y^2 = x +4 then 25y^2 = 25x +100So: 4x^2 -16x +16 = 25x +100Transposing terms: 4x^2 -41x -84 = 0Factorizing the above: (4x+7)(x-12) = 0 meaning x = -7/4 or x =12By substitution into original equation points of intersection:(-7/4, 3/2) and (12, -4)

Description : What is the perpendicular bisector equation of the line y equals 5x plus 10 spanning the parabola y equals x squared plus 4?

Last Answer : If: y = 5x +10 and y = x^2 +4Then: x^2 +4 = 5x +10Transposing terms: x^2 -5x -6 = 0Factorizing the above: (x-6)(X+1) = 0 meaning x = 6 or x =-1Therefore by substitution endpoints of the line are ... .5 = -1/5(x-2.25) => 5y= -x+114.75Perpendicular bisector equation in its general form: x+5y-114.75= 0

Description : What are the points of intersection between the line 3x -y equals 5 and the curve 2x squared plus y squared equals 129?

Last Answer : If: 3x-y = 5 then y^2 = (3x_5)^2 => 9x^2 -30x+25If: 2x^2 + y^2 = 129 then y^2 = 129-2x^2So: 9x^2 -30x+25 = 129-2x^2Transposing terms: 11x^2 -30x -104 = 0Factorizing the above: (11x- ... x = 52/11 or x= -2By substituting x into the original equation intersections areat: (52/11, 101/11) and (-2, -11)

Description : How do you graph y equals x squared plus 1?

Last Answer : Select a set of value of x in the range over which you wish todraw the graph. For each point, x, calculate x2+1 and then plot thepoint (x, x2+1) on a coordinate plane. Join these points with asmooth curve.

Description : What are the points of contact between the line x -2y equals 1 and the curve 4y squared -3x squared equals 1?

Last Answer : If: x-2y = 1 Then: x^2 = 4y^2 +4y+1 If: 4y^2 -3x^2 = 1 Then: 4y^2 -3(4y^2 +4y+1) = 1 Removing brackets: 4y^2 -12y^2 -12y -3 = 1 Transposing terms: -8y^2 -12y -4 = 0 Dividing all ... meaning y = -1/2 or -1 By substitution into original linear equation points of contact are at: (0, -1/2) and (-1, -1)

Description : If a cos theta plus b sin theta equals 8 and a sin theta - b cos theta equals 5 show that a squared plus b squared equals 89?

Last Answer : There is a hint to how to solve this in what is required to be shown: a and b are both squared.Ifa cos θ + b sin θ = 8a sin θ - b cos θ = 5then square both sides of each to get:a² cos² θ + 2ab cos ... + sin² θ) + b² (sin² θ + cos² θ) = 89using cos² θ + sin² θ = 1â†' a² + b² = 89

Description : The locus of points of intersection of the tangents to `x^(2)+y^(2)=a^(2)` at the extremeties of a chord of circle `x^(2)+y^(2)=a^(2)` which touches t

Last Answer : The locus of points of intersection of the tangents to `x^(2)+y^(2)=a^(2)` at the extremeties of a chord of circle ` ... ` C. `(a,0)` D. `((a)/(2),0)`

Description : The slope of one of the common tangent to circle `x^(2)+y^(2)=1` and ellipse `x^(2)/4+2y^(2)=1` is `sqrt(a/b)` where `gcd(a, b)=1` then `(a+b)/2` is e

Last Answer : The slope of one of the common tangent to circle `x^(2)+y^(2)=1` and ellipse `x^(2)/4+2y^(2)=1` is ` ... `gcd(a, b)=1` then `(a+b)/2` is equal to

Description : A parabola is drawn through two given points `A(1,0)` and `B(-1,0)` such that its directrix always touches the circle `x² + y^2 = 4.` Then, The locus

Last Answer : A parabola is drawn through two given points `A(1,0)` and `B(-1,0)` such that its directrix always touches the circle ... `(x^(2))/(5)+(y^(2))/(4)=1`

Description : What is the straight line which touches the circumference in a circle?

Last Answer : It is the tangent of the circle

Description : If a given line is tangent to the circle then perpendicular distance from centre of the circle is equal to radius of the circle solve the following :

Last Answer : If a given line is tangent to the circle then perpendicular distance from centre of the circle is equal to radius of the ... D. `x^(2)+y^(2)+6x+1=0`

Description : If a given line is tangent to the circle then perpendicular distance from centre of the circle is equal to radius of the circle solve the following :

Last Answer : If a given line is tangent to the circle then perpendicular distance from centre of the circle is equal to radius of the ... 0` D. `x^(2)+y^(2)-8y=0`

Description : What is x squared equals 200?

Last Answer : It is a quadratic equation in the one variable.

Description : What is the length of the circle radius if the circle is x2 plus y2 equals 1?

Last Answer : The center of the circle is at (0, 0) and its radius is thesquare root of 1 which is 1

Description : What is the center and the radius of the circle x2 plus y2 -4x -6y -3 equals 0?

Last Answer : Equation of circle: x^2 +y^2 -4x -6y -3 = 0Completing the squares: (x-2)^2 +(y-3)^2 = 16 square unitsTherefore center of circle is at (2, 3) and its radius is 4units

Description : What is the center and the radius of the circle x2 plus y2 equals 12x -10y -12?

Last Answer : Equation of circle: x^2 +y^2 = 12x-10y-12Completing the squares: (x-6)^2 +(y+5)^2 = 49So center of circle is at (6, -5) and its radius is 7 units

Description : Find the equation of the circle which touches the both axes in first quadrant and whose radius is a. -Maths 9th

Last Answer : circle of radius a touches both axis in 1st quadrant so its centre will be (a,a). ∴ Required equation ⇒(x−a)2+(y−a)2=a2 ⇒x2+a2−2ax+y2+a2−2ay=a2 ⇒x2+y2−2ax−2ay+2a2−a2=0 ⇒x2−y2−2ax−2ay+a2=0.

Description : Find the equation of the circle which touches the both axes in first quadrant and whose radius is a. -Maths 9th

Last Answer : Given that the circle of radius ‘a’ touches both axis. So, its centre is (a, a) So, the equation of required circles is : (x-a)2 + (y-a)2 = a2 ⇒ x2 - 2ax + a2+y2 - 2ay + a2 = a2 ⇒ x2 + y2 - 2ax - 2ay + a2 = 0

Description : Equation of tangent of the curve `y = 1 - e^(x//2)` at that point at which the curve crosses the y-axis, is :

Last Answer : Equation of tangent of the curve `y = 1 - e^(x//2)` at that point at which the curve crosses the y-axis, is ... `2x+y = 1` C. `x=-2y` D. None of these

Description : Find the equation of tangent of the curve ` x^(2)+y^(2)=5` at point (1, 2).

Last Answer : Find the equation of tangent of the curve ` x^(2)+y^(2)=5` at point (1, 2).

Description : Find the point on the curve` y^(2) = x` at which the tangent drawn makes an angle of `45^(@)` from X-axis.

Last Answer : Find the point on the curve` y^(2) = x` at which the tangent drawn makes an angle of `45^(@)` from X-axis.

Description : Find the co-ordinates of that point on the curve `x^(2)/a^(2)+y^(2)/b^(2) = 1` at which the tangent drawn is parallel to Y-axis.

Last Answer : Find the co-ordinates of that point on the curve `x^(2)/a^(2)+y^(2)/b^(2) = 1` at which the tangent drawn is parallel to Y-axis.

Description : Find the co-ordinates of that point on the curve`y^(2)=x^(2)(1-x)` at which the tangent drawn is perpendicular to X-axis.

Last Answer : Find the co-ordinates of that point on the curve`y^(2)=x^(2)(1-x)` at which the tangent drawn is perpendicular to X-axis.

Description : Find the co-ordinates of that point on the curve `x^(3)+y^(3)= a^(3)` at which the tangent drawn is parallel to X-axis.

Last Answer : Find the co-ordinates of that point on the curve `x^(3)+y^(3)= a^(3)` at which the tangent drawn is parallel to X-axis.

Description : What is 3a squared when a equals to -3?

Last Answer : 6

Description : What number squared equals 12769?

Last Answer : Need answer

Description : What is the ratio of surface area to volume for a sphere with the following measurements surface area equals 588 M squared volume equals 1372 m to the Third?

Last Answer : The ratio appears to be 588 to 1372 or 3 to 7 in its simplest form

Description : How do you factorize x squared plus 7x?

Last Answer : It is: x(x+7) when factorized

Description : What is the solution set of the equation x squared plus 3x - 46?

Last Answer : 49

Description : How do ypu factor X squared minus 13x plus 12?

Last Answer : It is x^2 -13x +12 = (x-1)(x-12) when factored

Description : What is X squared plus x plus x plus one?

Last Answer : It is the same as: x^2 +2x +1 and it is (x+1)(x+1) whenfactored

Description : How do ypu factor X squared minus 13x plus 12?

Last Answer : It is x^2 -13x +12 = (x-1)(x-12) when factored

Description : What is X squared plus x plus x plus one?

Last Answer : It is the same as: x^2 +2x +1 and it is (x+1)(x+1) whenfactored

Description : How do you re-write x squared plus 5x - 3 in vertex form?

Last Answer : 8

Description : The electric field of a point charge varies: w) linearly with distance and inversely with charge x) linearly with distance and inversely with charge squared y) linearly with charge and inversely with distance squared z) linearly with charge and inversely with distance 

Last Answer : ANSWER: Z -- LINEARLY WITH CHARGE AND INVERSELY WITH DISTANCE  

Description : For an infinite sheet of positive charge, the electric field lines: w) run parallel to the sheet of charge x) are perpendicular to the sheet of charge and point in toward the sheet y) are perpendicular to the sheet of charge and point away from the sheet z) fall off as one over r squared

Last Answer : ANSWER: Y -- ARE PERPENDICULAR TO THE SHEET OF CHARGE AND POINT AWAY  

Description : How do you solve for y and x when x plus y equals 45?

Last Answer : There are infinitely many solutions as x + y = 45 defines astraight line. Pick a value for x and you can calculate the y valueso that x + y = 45.It can be rearranged to get y in terms of x:x + y = 45→ -x + x + y = ... y valuewill be found.eg x = 1 → y = -1 + 45 = 44x = 25 → y = -25 + 25 = 20