Đáp án:
Giải thích các bước giải:
`a, (x+5)^2=9`
`=> x+5 = +-3`
`=>` \(\left[ \begin{array}{l}x+5=3\\x+5=-3\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}x=-2\\x=-8\end{array} \right.\)
`----------`
`b, 3x(2x-1)-2x+1=0`
`3x(2x-1)-(2x-1)=0`
`(3x-1)(2x-1)=0`
`=>` \(\left[ \begin{array}{l}3x-1=0\\2x-1=0\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}3x=1\\2x=1\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}x=\frac{1}{3}\\x=\frac{1}{2}\end{array} \right.\)
`----------`
`c, x^2+ 2x -35=0`
`x^2 +7x-5x-35=0`
`x(x+7)-5(x+7)=0`
`(x-5)(x+7)=0`
`=>` \(\left[ \begin{array}{l}x-5=0\\x+7=0\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}x=5\\x=-7\end{array} \right.\)
#Chii
#Team: Natural Science Boss
