Question

The area of a trapezium in $390sq.cm$. One of its parallel sides is $5cm$ longer than the other and the distance between them is $12cm$. Find the length of the parallel sides of the trapezium.

Answer 1

Let height be $h=12$cm, Area$=390$ sq.cm

Let smaller parallel side be $x$ and the other side be $x+5$

So, Area$=\frac{1}{2}h(x+x+5)$

$\Rightarrow 390=\frac{12}{2}(x+x+5)$

$\Rightarrow 390=12x+30$

$\Rightarrow 12x=360$

$\therefore x=\frac{360}{12}=30$

$\therefore$ Smaller side$=x=30$cm

other side is

$=x+5cm=30+5=35cm$cm

Hence length of parallel sides are $30$ cm and $35$ cm.