\(a.2x\left(x-3\right)+5\left(x-3\right)=0\\ < =>\left(x-3\right)\left(2x+5\right)=0\\ < =>\left[{}\begin{matrix}x-3=0\\2x+5=0\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=3\\x=-\dfrac{5}{2}\end{matrix}\right.\\ b.\left(x^2-4\right)-\left(x-2\right)\left(3-2x\right)=0\\ < =>\left(x-2\right)\left(x+2\right)+\left(x-2\right)\left(2x-3\right)=0\\ < =>\left(x-2\right)\left(x+2+2x-3\right)=0\\ < =>\left(x-2\right)\left(3x-1\right)=0\\ < =>\left[{}\begin{matrix}x-2=0\\3x-1=0\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=2\\x=\dfrac{1}{3}\end{matrix}\right.\)
\(c.\left(2x+5\right)^2=\left(x+2\right)^2\\ < =>\left(2x+5\right)^2-\left(x+2\right)^2=0\\ < =>\left(2x+5-x-2\right)\left(2x+5+x+2\right)=0\\ < =>\left(x+3\right)\left(3x+7\right)=0\\ < =>\left[{}\begin{matrix}x+3=0\\3x+7=0\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=-3\\x=-\dfrac{7}{3}\end{matrix}\right.\\ d.x^2-5x+6=0\\ < =>x^2-2x-3x+6=0\\ < =>x\left(x-2\right)-3\left(x-2\right)=0\\ < =>\left(x-2\right)\left(x-3\right)=0\\ < =>\left[{}\begin{matrix}x-2=0\\x-3=0\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=2\\x=3\end{matrix}\right.\\ e.2x^3+6x^2=x^2+3x\\ < =>2x^2\left(x+3\right)=x\left(x+3\right)\\ < =>2x^2\left(x+3\right)-x\left(x+3\right)=0\\ < =>\left(2x^2-x\right)\left(x+3\right)=0\\ < =>x\left(2x-1\right)\left(x+3\right)=0\\ < =>\left[{}\begin{matrix}x=0\\x=\dfrac{1}{2}\\x=-3\end{matrix}\right.\)
; 
;2x2 + 3 = 0 ; 4– 0,2x = 0
