Q30 of 46 Page 1

Construct a triangle ABC in which AB = 5 cm, BC = 6 cm and ∠ABC = 60°. Now construct another triangle whose sides are 5/7 times the corresponding sides of ∆ABC.


Steps of construction :


1. Draw a line AB = 5 cm


2. Draw ∠ABX = 60°.


3. Taking B as center and with radius = 6 cm draw an arc which intersects BX at C


4. Join AC to get ∆ABC


5. Below AB, make an acute angle ∠BAX


6. Along AX mark 7 (greater of 5 and 7 in 5/7) points A1, A2, A3, A4, A5, A6 and A7 at equal distances.


7. Join A7B


8. From point A5, make a line A5B' parallel to A7B , meeting AB at B'.[Choosing A5 because we need a 5 : 7 ratio]


9. From point B' draw a line B'C' parallel to BC.


10. AB'C' is the triangle, whose sides are five - seventh of ∆ABC


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