Step-by-step explanation:
x = price of pants
y = price of top
x + y = 36
x = (4/5)y
we use the second equation as substitute in the first
(4/5)y + y = 36
4y + 5y = 180
9y = 180
y = $20
x = (4/5)y = (4/5)×20 = 4×4 = $16
