Bài 1:
a) `(7xy^3)(-3/7x^2y^2)`
`=-3x^3y^5`
Hệ số : `-3`
Biến : `x^3y^5`
b) `1/4xyz(-2)^3x^3(yz)^2`
`=1/4 . (-8) xyz.x^3.y^2z^2`
`=-2x^4y^3z^3`
Hệ số : `-2`
Biến : `x^4y^3z^3`
Bài 2:
b)`3x(x-1)+2(x-1)=0`
⇔`(3x+2)(x-1)=0`
⇔\(\left[ \begin{array}{l}3x+2=0\\x-1=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}3x=-2\\x=1\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=\frac{-2}{3}\\x=1\end{array} \right.\)