Answer:
The value of (x + y)³ is 1728.
Step-by-step explanation:
First, you have to find the value of x + y :
x² + 2xy + y² = 144
x² + xy + xy + y² = 144
x(x + y) + y(x + y) = 144
(x + y)(x + y) = 144
(x + y)² = 144
x + y = √144
x + y = 12
Next, the value of (x + y)³ :
(x + y) = 12³ = 1728
