Question

The area of a trapezium is 280 sq. cm and its height is 35 cm. If one of its parallel
sides is longer than the other by 10 cm, find the lengths of the two parallel sides​.

Answer 1

Answer:

Given : area of trapezium = 280 sq.cm    ,     height = 35 cm

To Find : length of two parallel sides.

Let the length of one parallel side of trapezium is a.

So, length of other parallel side = a + 10

Given the area of trapezium = 280 sq.cm & the height = 35 cm

Now area of a trapezium =  $\frac{1}{2}$ × height × (sum of the parallel sides)  

                                 280  =  $\frac{1}{2} \times 35\times ( a + a + 10 )$

                                 $\frac{280\times 2 }{35} = 2a + 10$

                                8 x 2 = 2a + 10

                                16 - 10 = 2a

The length of one parallel side is ,

                                          a = 3

length of other parallel side is a + 10 ,

                                  a + 10 = 3 + 10

                                             = 13

Hence , length of two parallel side is 3 cm and 13 cm.

Answer 2

Here, it is given that

Area of trapezium $= 280 sq.cm$

and their height is $35cm$

As we have to find the lengths of the two parallel sides,

Let,

The length of one parallel side is 'a',

Therefore, the length for other parallel sides is $a+10.$

We know that,

Area of trapezium = $\frac{1}{2}$ × height × ( sum of the parallel sides)

$=>280=\frac{1}{2} \times 35\times (a+a+10)$

$=>\frac{280\times 2}{35} =2a+10$

$=>8\times 2=2a+10$

$=>16-10=2a$

$=>6=2a$

$=>a=3$

As the length of one parallel side will be a =3cm.

And the length of the other parallel side will be,

$=>a+10\\=>3+10\\=>13cm$

Therefore, the length of the two parallel sides will be $3cm$ and $13 cm$ respectively.