C1:
1/24 : (3x – 2) =-3
2/-45 : 5.(-3 – 2x)=3
3/x.(x + 7) =0
4/(x + 12).(x-3) =0
5/x.(2 + x).(7 – x) =0
6/(x-1).(x+2).(-x – 3) =0
C1: 1/24 : (3x – 2) =-3 2/-45 : 5.(-3 – 2x)=3 3/x.(x + 7) =0 4/(x + 12).(x-3) =0 5/x.(2 + x).(7 – x) =0 6/(x-1).(x+2).(-x – 3) =0
By Jade
1 24 : (3x – 2) =-3
⇔3x – 2=24 : (-3)
⇔3x – 2=-8
⇔3x =-8+2
⇔3x =6
⇔3x =6 : 3
⇔ x =1
Vậy x=1
2 -45 : 5.(-3 – 2x)=3
⇔-9.(-3 – 2x)=3
⇔ -3 – 2x =3:(-9)
⇔ -3 – 2x =-1/3
⇔ – 2x =-1/3+3
⇔ – 2x =8/3
⇔ x =8/3:(-2)
⇔ x =-4/3
3 x.(x + 7) =0
⇔\(\left[ \begin{array}{l}x=0\\x + 7=0\end{array} \right.\)⇔\(\left[ \begin{array}{l}x=0\\x=-7\end{array} \right.\)
Vây x=0; x=-7
4 (x + 12).(x-3) =0
⇔\(\left[ \begin{array}{l}x + 12=0\\x-3=0\end{array} \right.\)⇔\(\left[ \begin{array}{l}x=-12\\x=3\end{array} \right.\)
Vây x=-12; x=3
5 x.(2 + x).(7 – x) =0
⇔\(\left[ \begin{array}{l}x=0\\2 + x=0\end{array} \right.\)
hoặc 7 – x=0
⇔\(\left[ \begin{array}{l}x=0\\x=-2\end{array} \right.\)
hoặc x=7
Vậy x=0;x=-2;x=7
6 (x-1).(x+2).(-x – 3) =0
⇔\(\left[ \begin{array}{l}x-1=0\\ x+2 =0\end{array} \right.\)
hoặc x -3 =0
⇔\(\left[ \begin{array}{l}x=1\\x=-2\end{array} \right.\)
hoặc x=3
Vậy x=1;x=-2;x=3
1.
$24:(3x-2)=-3$
$3x-2=24:(-3)$
$3x-2=-8$
$3x=(-8)+2$
$3x=-6$
$x=(-6):3$
$→ x=-2$
2.
$-45:5.(-3-2x)=3$
$-9.(-3-2x)=3$
$-3-2x=3:(-9)$
$-3-2x=0,3$
$2x=(-3)-0,3$
$2x=-3,3$
$→ x=-1,65$
(Số 0,3 mình chỉ lấy xấp xỉ thôi nhé!)
3.
$x.(x+7)=0$
$2x+7x=0$
$9x=0$
$→ x=0$
4.
$(x+12).(x-3)=0$
$x+12=0⇒x=0-12=-12$
$x-3=0⇒x=0+3=3$
$\textrm{→ x={-12;3}}$
5.
$x.(2+x).(7-x)=0$
$x.(2+x)$
$2x+2x=0$
$4x=0$
$→ x=0$
$7-x=0$
$x=7-0$
$→ x=7$
$\textrm{→ x={0;7}}$
6.
$(x-1).(x+2).(-x-3)=0$
$x-1=0$
$→ x=0+1=1$
$x+2=0$
$→x=0-2=-2$
$-x-3=0$
$-x=0+3$
$-x=3$
$→ x=-3$
$\textrm{→ x={1;-2;-3}}$