A rectangle has a perimeter of 76 cm and length 31 cm what is its width

The formula for the perimeter of a rectangle is P = 2L + 2W

you are given P (perimeter) and l (length.

Replace the letters withe the given information and solve for width:

76 = 2 (31) + 2W

Simplify:

76 = 62 + 2w

Subtract 62 from both sides:

14 = 2w

Divide both sides by 2:

W = 14/2

W = 7 cm

The width is 7 cm.