Question

What is the simplified form of the rational expression below 6x^2-54 / 5x^2+15x

Answer 1

Answer:

$\large\boxed{\dfrac{6x^2-54}{5x^2+15x}=\dfrac{6(x-3)}{5x}=\dfrac{6x-18}{5x}}$

Step-by-step explanation:

$6x^2-54\qquad\text{distributive}\\\\=6(x^2-9)=6(x^2-3^2)\qquad\text{use}\ a^2-b^2=(a-b)(a+b)\\\\=6(x-3)(x+3)\\\\5x^2+15x\qquad\text{distributive}\\\\=5x(x+3)\\-----------------\\\\\dfrac{6x^2-54}{5x^2+15x}=\dfrac{6(x-3)(x+3)}{5x(x+3)}\qquad\text{cancel}\ (x+3)\\\\=\dfrac{6(x-3)}{5x}=\dfrac{6x-18}{5x}$