We know that, each angle of a square is right angle (i.e., 90°). To construct a square of side 3 cm, use the following steps. 1.Draw a line segment AS of length 3 cm. 2.Now, generate an angle of 90° at points A and B of the line segment and plot the parallel lines AX and BY at these points. 3.Cut AD and SC of length 3 cm from AX and BY, respectively. 4.Draw an angle of 90° at any one of the point C or D and join both points by a line segment CD of length 3 cm. Thus, ABCD is the required square of side, 3 cm. Alternate Method To construct a square ABCD of side 3 cm, use the following steps 1.Draw a line segment AB of length 3 cm. 2.Now, draw an angle XAB = 90° at point A of line segment AB. 3.Cut a line segment AD = 3 cm from the ray AX and join BD. 4.Now, from D point C is at a distance of 3 cm. So, having D as centre, draw an arc of radius 3 cm. 5.From B, point C is at a distance of 3 cm. So, having 8 as centre, draw an arc of radius 3 cm which intersect previous arc (obtained in step iv) at C. 6.Join DC and BC. Thus, ABCD is the required square of side 3 cm.