We know that FOIL means first outer inner and last. In this case that would be:
x^2 • x^2 = x^4
x^2 • 8 = 8x^2
-2 • x^2 = -2x^2
-2 • 8 = -16
Then you want to combine like terms, which in this case are:
8x^2 + (-2x^2) which is the same as
8x^2 - 2x^2 = 6x^2
Which would give us our final answer as:
x^4 + 6x^2 - 16
