Answer:
A) all values of x, and all values of y
B) (3a + 4b) (9a² − 12ab + 16b²)
Step-by-step explanation:
(x² + y²)² = (x² − y²)² + (2xy)²
x⁴ + 2x²y² + y⁴ = x⁴ − 2x²y² + y⁴ + 4x²y²
x⁴ + 2x²y² + y⁴ = x⁴ + 2x²y² + y⁴
27a³ + 64b³
(3a)³ + (4b)³
(3a + 4b) (9a² − 12ab + 16b²)