Tìm x, biết 4(3x - 1) - 2(5 - 3x) = -12

tìm x biết
$$\begin{gathered} a) 4\left(3x-1\right)-2\left(5-3x\right)=-12 \\ b) 2x\left(x-1\right)-3\left(x^2-4x\right)+x\left(x+2\right)=-3 \\ c) \left(x-1\right)\left(2x-3\right)-\left(x+3\right)\left(2x-5\right)=4 \\ d)\left(6x-3\right)\left(2x+4\right)+\left(4x-1\right)\left(5-3x\right)=-21 \end{gathered}$$