Question

the lengths of parallel sides of trapezium are in the ratio 7:5 and the distance between them is 14 cm. if the area of the trapezium is 252 cm square, find the lengths of its parallel sides.

Answer 1

Area of trapezium = 252 cm²
Dimension of parallel side = 7x & 5x
Height = 14cm

Area of Trapezium= ½ Height (sum of parallel side)
252cm²=½×14(7x+5x)
252cm²=7×12x
252cm²=84x
252cm²/84=x
3=x

$7x = 7 \times 3 = 21 \\ 5x = 5 \times 3 = 15$

Answer 2

Let one side be (a)=7x                    

another side be (b)= 5x    

height (h)=14cm.

Area of trapezium =252cm^2 .

i e. h/2(a+b)=252cm^2 .

14/2(7x+5x)=252cm^2 .

7(12x)=252cm^2 .

∴x=252/7*12

∴ x=3

One side (7x)=7*3=21cm. ...........ANS

another side (5x)=5*3=15cm.......ANS