Đáp án:
Giải thích các bước giải:
a,
5(x-2)=3x+10
⇔5x-10-3x-10=0
⇔2x-20=0
⇔2x=20
⇔x=10
b,⇔$\frac{3x-15}{12}$+$\frac{8x-8}{12}$-$\frac{6-6x}{12}$=0
⇔$\frac{3x-15+8x-8-6+6x}{12}$=0
⇔$\frac{17x-29}{12}$ =0
⇔17x-29=0
⇔17x=29
⇔x=$\frac{29}{17}$
c,
⇔ $\left \{ {{4x-2=0} \atop {3x+1=0}} \right.$
⇔$\left \{ {{4x=2} \atop {x=-$\frac{1}{3}$ }} \right.$
⇔$\left \{ {{x=$\frac{1}{2}$ } \atop {x=-$\frac{1}{3}$}} \right.$
d,
⇔x(x-7)-2020(7-x)=0
⇔x(x-7)+2020(x-7)=0
⇔(x-7)(x+2020)=0
⇔\(\left[ \begin{array}{l}x-7=0\\x+2020=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=7\\x=-2020\end{array} \right.\)
