Answer:
x² + 3x - 28
Step-by-step explanation:
We need f(x)*g(x), or
(x + 7)(x - 4)
Use FOIL to multiply, Foil is Firsts, Outsides, Insides, Lasts. It tells you the terms to multiply together...
Firsts: x(x) = x²
Outsides: x(-4) = -4x
Insides: 7(x) = 7x
Lasts: (7)(-4) = -28
So we have
x² - 4x + 7x - 28
simplify to
x² + 3x - 28