Question

Area of trapezium is 28 m² and two parallel sides are 8m and 60 DM respectively find the altitude.

Answer 1

Given :

Area of trapezium = 28 m²

Two parallel sides are 8 m and 60 dm respectively.

Find :

The altitude of the trapezium.

Solution :

We know that..

$\boxed{ \bold{Area \: of \: trapezium \: = \: \frac{1}{2} \: \times \: h(a \: + \: b)}}$

Where..

• h = height (altitude)

• a and b = parallel sides of the trapezium

8 m and 60 dm are the parallel sides.

Now,

1 m = 10 dm

So,

8 m and 6 m are the parallel sides.

Put the known values in above formula

$\Rightarrow\:28\:=\:\dfrac{1}{2}\:\times\:h(8\:+\:6)$

$\Rightarrow\:28\:=\:\dfrac{1}{2}\:\times\:h(14)$

$\Rightarrow\:28\:=\:7h$

$\Rightarrow\:h\:=\:\dfrac{28}{7}$

$\Rightarrow\:h\:=\:4$

∴ Altitude of the trapezium is 4 m

_____________________________

☆ Verification :

From above calculations we have h (altitude) = 4 m.

Also, Area of trapezium is 28 m² and parallel sides are 8 m and 6 m.

So,

==> Area of trapezium = 1/2 × h(a + b)

=> 28 = 1/2 × 4(8 + 6)

=> 28 = 2(14)

=> 28 = 28