Question

What is the factoring quadratic expression for 8x^2-18=0

Answer 1

$8x^2-18=0\\ 2(4x^2-9)=0\\ 2(2x-3)(2x+3)=0\\ x=\frac{3}{2} \vee x=-\frac{3}{2}$

Answer 2

$8x^2-18=0\ /:2\\\\4x^2-9=0\ \ \ \Leftrightarrow\ \ \ (2x)^2-3^2=0\ \ \ \Leftrightarrow\ \ \ (2x-3)(2x+3)=0\\\\2x-3=0\ \ \ \ \ \ \ or\ \ \ \ 2x+3=0\\\\2x=3\ /:2\ \ \ \ \ \ or\ \ \ \ 2x=-3\ /:2\\\\x=1.5\ \ \ \ \ \ \ \ \ \ \ \ or\ \ \ \ x=-1.5$