Question

If the width of a rectangle is 3 and the perimeter is 20 what is the missing side length

Answer 1

The formula to find the perimeter of a rectangle is:

P = 2(l + w)

plug in your known values to solve for the unknown

20 = 2(l + 3)
20 = 2l + 6
14 = 2l
14/2 = l
7 = l or l = 7

you can check this by plugging your l value into the equation

P = 2(l + w)
20 = 2(7 + 3)
20 = 2(10)
20 = 20

hope this helps :)