Question

(5x^2-7y-9)-(8x^2-6y-2) what's the difference?

Answer 1

Group together the like terms.
5x^2 - 7y - 9 - 8x^2 + 6y + 2
= 5x^2 - 8x^2 - 7y + 6y - 9 + 2
= -3x^2 - y - 7

Answer 2

i believe you can foil this equation, but instead of multiplying you subtract