Question

4x^2 -9

Answer 1

\(4x^2-9=\left(2x\right)^2-3^2=\left(2x-3\right)\left(2x+3\right)\)

Answer 2

4x² - 9 =0

<=> ( 2x +3 ) ( 2x- 3 ) =0

<=> \(\orbr{\begin{cases}2x+3=0\\2x-3=0\end{cases}}\)

<=> \(\orbr{\begin{cases}2x=-3\\2x=3\end{cases}}\) 

<=> \(\orbr{\begin{cases}x=\frac{-3}{2}\\x=\frac{3}{2}\end{cases}}\)