How can i simplify this equation? Answer in steps, please.

Question

(r+q)(r-q)-r²

^{_____________}

3q²

Answer 1

((r+q)(r-q)-r^2)/(3q^2) (distribute)

(r^2-q^2-r^2)/(3q^2) (r^2 cancel out)

-q^2/(3q^2) (q^2 cancel out)

-1/3

I hope it helps! :)

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