Simplify the given expression. (5x + 8y) (25x2 + 64y2 - 40xy)

125x3 - 512y3 25x3 + 64y3 125x3 + 512y3 25x3 - 64y3

125x3 + 512y3

(a³ + b³) = (a + b)(a² + b² - ab) = (5x + 8y) (25x2 + 64y2 - 40xy) = (5x + 8y)[(5x)² + (8x)² - 8 × 5 xy] = (5x)³ + (8y)³ = 125x³ + 512y³