Construct and simplify difference quotient?

Question

For the function

f(x)=8−x^2​, construct and simplify the difference quotient f(x+h)−f(x)/ h

Answer 1

f(x+h) = 8 - (x+h)^2 = 8 - x^2 -2xh - h^2

f(x+h) - f(x) = 8 - x^2 -2xh - h^2 - (8 - x^2)

= 8 - x^2 -2xh - h^2 - 8 + x^2

= 2xh - h^2

divided by h: 2x - h