The perimeter of a parallelogram is 50 cm. The length of the parallelogram is 5 cm more than the width. Find the length of the parallelogram.

Let w = the width of the parallelogram and let l = the length of the parallelogram. Because the length is 5 more than the width, then l = w + 5. The formula for the perimeter of a parallelogram 2l + 2w = 50. Substituting the ?rst equation within the second for l results in 2(w + 5) + 2w = 50. Use the distributive property on the left side of the equation: 2w + 10 + 2w = 50; merge like terms on the left side of the equation: 4w + 10 = 50. Subtract 10 on both sides of the equation: 4w + 10 - 10 = 50 - 10. Simply to: 4w = 40. Divide both sides of the equation through 4: 4w/4 = 40/4; w = 10. Thus, the width is 10 cm and the length is 10 + 5 = 15 cm.