Q79 of 131 Page 226

Ratio of the area of ∆WXY to the area of ∆WZY is 3 : 4 (Fig. 9.33). If the area of ∆WXZ is 56 cm2 and WY = 8 cm, find the lengths of XY and YZ.

We know that, area of a triangle = × b × h


Given, Area of ∆WXZ = 56 cm2


× XZ × 8 = 56


XZ = = 14 cm


∵






4XY = 42 – 3XY


7XY = 42


XY = 6 cm


YZ = XZ – XY = 14 – 6 = 8 cm


So, XY = 6 cm and YZ = 8 cm


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