Question

If the perimeter of a rectangle is 26cm and it's breadth is 4cm it's length is now going to be what

Answer 1

The perimeter of the rectangle is given as;

the breadth is also given as;

`b\text{ = 4cm}`

Recall that the formula for the perimeter of a restangle is;

`P=\text{ 2(l+b) = 2l + 2b}`

where,

l is the length and b is the breadth

So, let us substitute the values of P and b into the formula;

`\begin{gathered} P=2l+2b \\ 26=2l+2(4) \\ 26=2l+8 \end{gathered}`

Now, let us solve for l;

`\begin{gathered} 26=2l+8 \\ \text{subtract 8 from both sides.} \\ 26-8=2l+8-8 \\ 18=2l \\ \text{divide both side by 2;} \\ (2l)/(2)=(18)/(2) \\ l=9\text{ cm} \end{gathered}`

Therefore the length of the of the rectangle is 9cm