\(\left(x.7-7\right)\left(x.12+24\right)=0\)
=> \(\orbr{\begin{cases}x.7-7=0\\x.12+24=0\end{cases}}\)
=> \(\orbr{\begin{cases}7x=7\\12x=-24\end{cases}}\)
=> \(\orbr{\begin{cases}x=1\\x=-2\end{cases}}\)
\(170-\left(4+5x\right)=101\)
=> \(4+5x=170-101\)
=> \(4+5x=69\)
=> \(5x=69-4\)
=> \(5x=65\)
=> \(x=65:5=13\)
(x.7-7).(x.12+24)=0
* x.7-7=0 * x.12+24=0
x.7=7 x.12=24
x=7:7 x=24:12
x=1 x=2
vạy x=1 hoặc x=2
170-(4+5x)=101
4+5x=170-101
4+5x=69
5x=69-4
5x=65
x=65:5
x=13
vậy x=13
250:(2x-4)=145-120
250:(2x+4)=25
2x+4=250:25
2x+4=10
2x=10+4
2x=14
x=14:2
x=7
vậy x=7
6.x+3.x-4.x=105
x.(6+3-4)=105
x.(9-4)=105
x.5=105
x=105:5
x=21
vậy x=21
1) (x.7 - 7)(x.12 + 24) = 0
(7x - 7)(12x + 24) = 0
7x - 7 = 0 hoặc 12x + 24 = 0
7x = 0 + 7 12x = 0 - 24
7x = 7 12x = -24
x = 1 x = -2
Vậy: x = 1 hoặc x = -2
2) 170 - (4 + 5x) = 101
170 - 4 - 5x = 101
-5x + 166 = 101
-5x = -65
x = 13
3) 250 : (2x - 4) = 145 - 120
250 : (2x - 4) = 25
125 = 25(x - 2)
125 : 25 = x - 2
5 = x - 2
5 + 2 = x
7 = x
x = 7
4) 6.x + 3.x - 4.x = 105
5.x = 105
x = 105 : 5
x = 21
\(\left(x.7-7\right).\left(x.12+24\right)=\) \(0\)
\(\Rightarrow\orbr{\begin{cases}x.7-7=0\\x.12+24=0\end{cases}}\) \(\Rightarrow\orbr{\begin{cases}x.7=0+7\\x.12=0-24\end{cases}}\) \(\Rightarrow\orbr{\begin{cases}x.7=7\\x.12=-24\end{cases}}\) \(\Rightarrow\orbr{\begin{cases}x=7:7\\x=-24:12\end{cases}}\) \(\Rightarrow\orbr{\begin{cases}x=1\\x=-2\end{cases}}\)
\(170-\left(4+5x\right)=101\)
\(4+5x=170-101\)
\(4+5x=69\)
\(5x=69-4\)
\(5x=65\)
\(x=65:5\)
\(\Rightarrow x=13\)
\(250:\left(2x-4\right)=145-120\)
\(250:\left(2x-4\right)=25\)
\(2x-4=250:25\)
\(2x-4=10\)
\(2x=10+4\)
\(2x=14\)
\(x=14:2\)
\(\Rightarrow x=7\)
\(6.x+3.x-4.x=105\)
\(\left(6+3-4\right).x=105\)
\(5.x=105\)
\(x=105:5\)
\(\Rightarrow x=21\)