Question

If the length of a rectangle exceeds it's breadth by 10metres.Its perimeter is 40 m
​

Answer 1

Answer:

l=15,b=5

Step-by-step explanation:

l=b+10

b=?

p=40m

p=2(l+b)

40=2(b+10+b)

40=4b+20

40-20=4b

20=4b

b=5

l=b+10

l=5+10

l=15

Answer 2

Answer:

Breadth = 5m

Length = 15m

Step-by-step explanation:

Given:

➝ Perimeter = 40 m

To Find:

➝ Length = ?

➝ Breadth = ?

Procedure:

Let's assume breadth to be x m.

It's given that the length exceeds its breadth by 10 m. In other words, length is 10 m more than it's breadth.

From the given info, we can infer that;

Length = ( x + 10 )m

We know that;

Perimeter = 2( length + breadth )

$\sf \implies 40 = 2(x + x + 10)$

$\implies \sf 40 = 2(x) + 2(x) + 2(10)$

$\implies \sf 40 = 2x + 2x +20$

$\implies \sf 40 = 4x + 20$

Now, for the sake of simplicity — let's flip the equation :-

$\implies \sf 4x + 20 -20 = 40-20$

$\implies \sf 4x = 20$

Divide both sides by 4;

$\implies \sf \dfrac{4x}{4}= \dfrac{20}{4}$

$\sf \implies x = 5m$

xm = breadth = 5m

xm + 10m = Length = 5m + 10m = 15m

To solve a word problem you follow following steps :

1. The very first step is to understand the problem. Just like a human has his language , a mathematics problem too have. So , understand that language.
2. Assign variable to unknown quantity.
3. Translate it to mathematical sentence.
4. Solve the equation for unknown.