The length of a rectangle is 10cm greater than the width. The area is 551cm^2. Find the length and width

width: w

length: w+10
area: width*length

w(w+10) = 551
w^2 + 10w - 551 = 0
551 = 19*29
(w-19)(w+29) = 0

w = 19 or -29

-29 makes no physical sense, so the rectangle is 19x29