\(a.2\left(x+3\right)-x\left(x+3\right)=0\)
\(\text{⇔}\left(x+3\right)\left(2-x\right)=0\)
\(\text{⇔}x=-3orx=2\)
\(b.x^2\left(2x+3\right)-8x-12=0\)
\(\text{⇔}x^2\left(2x+3\right)-4\left(2x+3\right)=0\)
\(\text{⇔}\left(x-2\right)\left(x+2\right)\left(2x+3\right)=0\)
\(\text{⇔}x=2;x=-2orx=-\dfrac{3}{2}\)
\(c.\left(2x-7\right)^2-\left(x-3\right)^2=0\)
\(\text{⇔}\left(2x-7-x+3\right)\left(2x-7+x-3\right)=0\)
\(\text{⇔}\left(x-4\right)\left(3x-10\right)=0\)
\(\text{⇔}x=4orx=\dfrac{10}{3}\)
\(d.\left(5x^2+3x-2\right)^2=\left(4x^2-3x-2\right)^2\)
\(\text{⇔}\left(5x^2+3x-2-4x^2+3x+2\right)\left(5x^2+3x-2+4x^2-3x-2\right)=0\)
\(\text{⇔}\left(x^2+6x\right)\left(9x^2-4\right)=0\)
\(\text{⇔}x\left(x+6\right)\left(9x^2-4\right)=0\)
\(\text{⇔}x=0;x=-6orx=+-\dfrac{2}{3}\)
Còn lại tượng tự nha , dài quá ~
a) 2(x+3)=x(x+3)
2x+6=x^2+3x
2x-x^2-3x=6
x(2-x-3)=6
x(-1-x)=6 ( xong lập bang nhà)