Question

The parallel sides of an isoseles trapezium are in the ratio $2:3$ . If its height is $4cm$ and area is $60c{m}^2$, find the perimeter.

Answer 1

REF.Image

Let x be the proportion.

Area = $60c{m}^2$

$60=\frac{1}{2}(2x+3x)\times 4$

$5x=30\Rightarrow x=6m$

$\therefore B_1=3\times 6=18cm$ $B_2=2\times 6=12cm$

perimeter = 12+y+18+y

$y=\sqrt{4^2+3^2}=5cm$

$\therefore$ perimeter = 12+5+18+5 = 40 cm