Answer:
x² + 3x - 28
Step-by-step explanation:
Each term in the second factor is multiplied by each term in the first factor
(x + 7)(x - 4)
= x(x - 4) + 7(x - 4) ← distribute both parenthesis
= x² - 4x + 7x - 28 ← collect like terms
= x² + 3x - 28
