Question

Please help i’m struggling!

the length of a rectangular piece of steel in a bridge is 5 meters less than double the width. The perimeter of the piece of steel is 38 meters. Find the length and width of the piece of steel.

Answer 1

Let Breadth = x

We know :
- Perimeter = 38 m
- Length (in terms of breadth) = 2x - 5

Let’s do it in Linear Equation form…

Perimeter formula : 2 * (l + b)

Therefore, 2 * (2x - 5 + x) = 38



2 * (2x - 5 + x) = 38

2. Then multiply the ‘l+b’ with 2
: 4x - 10 + 2x = 38

3. Add 10 to both the sides
: 4x - 10 + 2x + 10 = 38 + 10
: 4x + 2x = 48

4. Add the LHS up
: 6x = 48

5. Divide both the sides with 6
: 6x / 6 = 48 / 6
: x = 8

Now we know the breadth = 8
And we already know length = 2x - 5
So…

2x - 5
= 2 * 8 - 5
= 16 - 5
= 11

Length = 11 m
Breadth = 8 m

VERIFICATION :

2 * (11 + 8)
= 2 * 19
= 38 m


Hope you got your answer!