Question

x(2x-3)-(4x^2-9)=0

Answer 1

\(x\left(2x-3\right)-\left(4x^2-9\right)=0\\ \Rightarrow x\left(2x-3\right)-\left(2x-3\right)\left(2x+3\right)=0\\ \Rightarrow\left(2x-3\right)\left(x+3\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=-3\end{matrix}\right.\)

Answer 2

\(\Leftrightarrow\left(2x-3\right)\left(x+3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=-3\end{matrix}\right.\)

Answer 3

x(2x-3)-(4x²-9)=0

x(2x-3)-[(2x)²-3² ] = 0

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

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

Khi và chỉ khi:

x= 0 hoặc 2x-3=0 hoặc 2x+3= 0 

                 2x=3    hoặc   2x= -3

                 x=3/2 hoặc   x= -3/2

Vậy x= 0; x= 3/2; x=-3/2