Answer:
7x³y - 35x² + 35y² + 48x²y² - 240xy - 7xy³
Explanation:
Dimensions of the cube = (x+7y),(7x-y) and (xy-5)
Volume of the cube = (x+7y) (7x-y) (xy-5)
= (7x² - xy + 49xy - 7y²)(xy - 5)
= 7x³y - 35x² - x²y² + 5xy + 49x²y² - 245xy - 7xy³ + 35y²
= 7x³y - 35x² + 35y² + 49x²y² - x²y² + 5xy - 245xy - 7xy³
= 7x³y - 35x² + 35y² + 48x²y² - 240xy - 7xy³
Volume of the cube = 7x³y - 35x² + 35y² + 48x²y² - 240xy - 7xy³