How do you expand and simplify (x − 6)(x + 2y)^2

start of by expanding the braquet which has got a power(x + 2y) (x + 2y) = X² + 2xy + 2xy + 4Y²then simplify that => x² + 4xy + 4y²then multiply that by (x - 6) (x - 6) (x² + 4xy + 4y²) = x³ + 4x²y + 4xy² - 6x² - 24xy - 24y²then simplify it (in this case this is as simplified as it gets x³ + 4x²y + 4xy² - 6x² - 24xy - 24y²