Andrew M. answered 03/25/17
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
Area of a rectangle is length times width... A = LW
LW = 140
W = L/2 + 3
Replace W with L/2 + 3 in first equation and solve for L
L(L/2 + 3) = 140
L2/2 + 3L = 140
multiply through by 2
L2 + 6L = 280
L2 + 6L - 280 = 0
Factors of -280 that add to 6 are 20(-14)
(L+20)(L-14) = 0
L = -20 or L = 14
Discarding the negative, the length is 14 meters
W = L/2 + 3 = 10 meters
The garden is 14 by 10 meters