Draw a parallelogram ABCD in which BC=5 cm, AB=3 cm, and ABC=60°, divide it into triangles BCD and ABD by the diagonal BD. Construct the triangles BDC similar to ∆BDC with scale factor 4/3. Draw the line segment D’A’ parallel to DA, where A’ lies on extended side BA. Is A’BC’D’ a parallelogram?


Steps of construction


1. Draw a line AB=3 cm.


2. Draw a ray BY making an acute ABY=60°.


3. With B as center and radius equal to 5 cm draw an arc cut the point C on BY.


4. Draw a ray AZ making an acute ZAX=60°.(BY││AZ, YBX=ZAX=60°)


5. With A as center and radius equal to 5 cm draw an arc cut the point D on AZ.


6. Join CD and finally make a parallelogram ABCD.


7. Join BD, which is a diagonal of parallelogram ABCD.


8. Draw any ray BX downwards making an acute CBX.


9. Locate 4 points B1,B2,B3,B4 on BX, such that BB1=B1B2=B2B3=B3B4.


10. Join B4C and from B3C draw a line B4C’||B3C intersecting the extended line segment BC at C’.


11. Draw C’D’CD intersecting the extended line segment BD at D’. Then, ∆D’BC’ is the required triangle whose sides are 4/3 of the corresponding sides of ∆DBC.


12. Now draw a line segment D’A’DA, where A’ lies on the extended side BA


13. Finally, we observe that A’BC’D’ is a parallelogram in which A’D’=6.5 cm A’B = 4 cm and ABD= 60° divide it into triangles BCD and ABD by the diagonal BD.



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