Question

The formula p = 2i + 2w means that the perimeter of a rectangle is equal to twice the sum of its length and its width.

Solve p = 2i + 2w for i

Answer 1

p = 2i + 2w

Subtract 2w from each side:

p-2w = 2i

Divide both sides by 2:

p-2w / 2 = i

Answer 2

`\boxed{i=(P-2w)/(2)=(P)/(2)-w}`

Explanation:

l - length

w - width

`2l+2w=P\qquad\text{subtract 2w from both sides}\\\\2l-2w-2w=P-2w\\\\2l=P-2w\qquad\text{divide both sides by 2}\\\\\boxed{l=(P-2w)/(2)}\\\\or\\\\l=(P)/(2)-(2w)/(2)\\\\\boxed{l=(P)/(2)-w}`