Question

7. The perimeter of a parallelogram is 140 cm. If one of the sides is longer than the other by 10 cm, find the length of each of its sides.

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Answer 1

The perimeter of a parallelogram is 140 cm. If one of the sides is longer than the other by 10 cm.

Let smaller side (a) =x then longer side (b)=x+10

Perimeter =2(a+b)=2(x+x+10)=140

=> x=30

Smaller side =30cm Larger side =30+10=40 cm

Answer 2

Given :-

• The perimeter of parallelogram is 140 cm.

• If one of the side is longer than the other by 10 cm

To find :-

• The length of each of its sides

Solution :-

Let the length of one side be x cm

and the length of other side be (x + 10) cm

Now,

we know that,

$\blue{\bigstar}\:\:{\underline{\boxed{\bf\red{Perimeter=2(length+breadth)}}}}$

$\rm\longrightarrow\:140=2\{x+(x+10)\}$

$\rm\longrightarrow\:140=2(2x+10)$

$\rm\longrightarrow\:140=4x+20$

$\rm\longrightarrow\:140-20=4x$

$\rm\longrightarrow\:120=4x$

$\rm\longrightarrow\:\cancel\dfrac{120}{4}=x$

$\rm\longrightarrow\:30=x$

$\rm\longrightarrow\:x=30$

∴ x = 30

and,

• x + 10

⤇ 30 + 10

⤇ 40

Hence,the length of each of its sides are 30 cm and 40 cm.