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            Construction of Rectangle

            Example 31: Construct a rectangle PQRS in which PQ = 5.4 cm and diagonal PR = 6.3 cm.
            Solution: We know that each angle of rectangle = 90° and opposite sides are equal. Using this
            property of rectangle, we may proceed with the given steps.

            Steps of construction:
            Step 1: Draw a line segment PQ = 5.4 cm.

            Step 2: At points P and Q, draw ∠QPX = ∠PQY = 90°.
            Step 3: Taking P as centre and radius = 6.3 cm, draw an arc
            intersecting QY at R. Join RP.
            Step 4: Taking P as centre and radius equal to QR, draw an arc
            that will intersect PX at S.

            Step 5: Join RS.
            Thus, PQRS is the required rectangle.
            Construction of Square

            Example 32: Construct a square ABCD whose side BC = 4.5 cm.

            Solution: Steps of construction:
            Step 1: Draw a line segment BC = 4.5 cm.

            Step 2: At B, construct ∠CBP = 90°.
            Step 3: From BP, cut off BA = 4.5 cm.

            Step 4: With C as centre and radius = 4.5 cm, draw an arc.
            Step 5: With A as centre and radius = 4.5 cm, draw an arc to
            meet the previous arc at D.
            Step 6: Join AD and CD.

            Thus, ABCD is the required square.
            Construction of Rhombus

            Example 33: Construct a rhombus ABCD, where AC = 7 cm and BD = 8 cm.

            Solution: We know that diagonals of a rhombus are perpendicular bisectors of each other. Using
            this property of rhombus, we proceed as follows.

            Steps of construction:
            Step 1: Draw a line segment AC = 7 cm, and then construct PQ, the
            perpendicular bisector of AC.
            Step 2: Let PQ and AC intersect each other at O.

                                                     1
            Step 3: Take O as centre and radius = (     × 8) cm = 4 cm. Draw two arcs
                                                     2
            on either side of AC which intersect PQ at the points B and D.
            Step 4: Join AB, BC, CD and DA.

            Thus, ABCD is the required rhombus.

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