math help please

Question

Rationalize the denominator and simplify completely: fraction numerator x squared minus 81 over denominator square root of x minus 3 end fraction

Answer 1

(x^2-81)/ sqrt(x-3) =

(x^2-81)*sqrt(x-3) / (x-3) =

(x^2+9)(x+3)(x-3)*sqrt(x-3)/(x-3) =

(x^2-9)(x+3)*sqrt(x-3)