Step-by-step explanation:
length = l
width = w
perimeter of garden = 76 ft
perimeter = 2l + 2w
2l + 2w = 76 (eqn 1)
l - w = 12 (eqn 2)
(eqn 1) ÷ 2
l + w = 38 (eqn 3)
(eqn 2) + (eqn 3)
2l = 50
2l/2 = 50/2
l = 25
The length of the garden is 25 ft.
Substitute l = 25 into (eqn 3)
l + w = 38
25 + w = 38
w = 38 - 25
w = 13
The width of the garden is 13 ft.
