The width of a rectangle is 10 feet more than 3 times its length. If the area of the rectangle is 217 square feet, then find the length and width.

Question

find the length and width

Answer 1

217 = LW = (3L+10)L = 3L^2 +10L

3L^2 + 10L - 217 = 0

L = -10/6 + or - (1/6)sqr(100+12(217)

L =-5/3 + or - (1/6)sqr

L =(-5 +26)/3 = 21/3 = 7 feet long

W = 10+3(7) = 31 feet wide

31 x 7 = 217