The sum of two numbers is 77. the greater number is 5 more than the smaller number. which equation can be used to solve for the smaller number?

x(x − 5) = 77
x(x + 5) = 77
x − (x + 5) = 77
x + (x + 5) = 77

simplify (x + 2)(x2 − 4x − 9).

x3 − 2x2 − 17x − 18
x3 − 6x2 − x − 18
x3 − 4x2 − 3x − 18
x3 − 10x2 − 9x − 18