Question

Write a formula for the given measure. Let P represent the perimeter in inches, and w

Answer 1

PERIMETER = 2 (LENGTH + WIDTH)
PERIMETER = 2 LENGTH + 2 WIDTH

Given: Length 5 inches

P = 2(5 in) + 2w
P = 10 in + 2w

Perimeter is dependent in both length and width. Changes in any length of width will automatically change perimeter.

For find width using the perimeter formula:

P = 10 + 2w
P - 10 = 2w
(P-10)/2 = w
P/2  - 5 = w

w = P/2  -  5

If the perimeter and length is given, you can use the derived formula to solve for width.