Assume that no denomenator equals 0.

(7x^2+3x-9)-(-x^2+8x-3)

= 7x^2+3x-9+x^2-8x+3
= (7x^2+x^2)+(3x-8x)+(-9+3)
= 8x^2+-5x+-6
= 8x^2-5x-6(answer)

4 answers

What exactly is your question? I don't even see a denominator anywhere :)

What you have is right so far. If you want to finish that question you need to use the quadratic formula

x = (-b +/- square root(b^2 - 4ac)) / 2a

x = (5 +/- square root (25 + 192)) / 16

x = (5 +/- square root (217)) / 16

which yields x1 = 1.23 and x2 = -0.61
(7x^2+3x-9)-(-x^2+8x-3) is the question. the rest is my work
Your solution is perfect, did you just want confirmation?
yes