3x+17=12
Tìm x, biết a. 0,5x -2/3x=7/12 b. -8/17+5/17<x/17<-6/17+9/17 c. [x-5/12].9/29=-6/29
\(a,0,5x-\frac{2}{3}x=\frac{7}{12}\Rightarrow\frac{1}{2}x-\frac{2}{3}x=\frac{7}{12}\)
\(\Rightarrow x\left(\frac{1}{2}-\frac{2}{3}\right)=\frac{7}{12}\Rightarrow x\cdot\left(\frac{3}{6}-\frac{4}{6}\right)=\frac{7}{12}\)
\(\Rightarrow x\cdot\left(-1\right)=\frac{7}{12}\Rightarrow x=\frac{7}{12}:\left(-1\right)=\frac{7}{-12}\)
\(c,\frac{\left(x-5\right)}{12}\cdot\frac{9}{29}=\frac{-6}{29}\Rightarrow\frac{\left(x-5\right)}{12}=\frac{-6}{29}:\frac{9}{26}\)
\(\frac{\Rightarrow\left(x-5\right)}{12}=\frac{-6}{9}=\frac{-2}{3}\Rightarrow x-5=-\frac{2}{3}\cdot12\)
\(\Rightarrow x-5=\frac{-24}{3}=-8\Rightarrow x=-8+5=-3\)
\(a,0,5x-\frac{2}{3}x=\frac{7}{12}\)
\(\Rightarrow\frac{1}{2}x-\frac{2}{3}x=\frac{7}{12}\)
\(\Rightarrow-\frac{1}{6}x=\frac{7}{12}\)
\(\Rightarrow x=-\frac{7}{2}\)
\(c,\frac{x-5}{12}\cdot\frac{9}{29}=-\frac{6}{29}\)
\(\Rightarrow\frac{x-5}{12}=-\frac{2}{3}\)
\(\Rightarrow x-5=12.\left(-\frac{2}{3}\right)\)
\(\Rightarrow x-5=-8\)
\(\Rightarrow x=-3\)
b)\(\frac{-8}{17}+\frac{5}{17}< \frac{x}{17}< \frac{-6}{17}+\frac{9}{17}\)\(\left(x\in Z\right)\)
\(\Rightarrow\frac{-3}{17}< \frac{x}{17}< \frac{3}{17}\)
\(\Rightarrow-3< x< 3\)
\(\Rightarrow x\in\left\{-2;-1;0;1;2\right\}\)
Vậy \(x\in\left\{-2;-1;0;1;2\right\}\)
3x+17=12
3x + 17 = 12
3x = 12 - 17
3x = -5
x = (-5).3
x = -15
3x + 17 = 12
3x = 12 - 17
3x = -5
x = -5 : 3
x = -1.66666667
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(\Leftrightarrow x^3-27-3x+17=x^3-12\)
\(\Leftrightarrow-10-3x=-12\)
\(\Leftrightarrow3x=2\)
\(\Leftrightarrow x=\dfrac{2}{3}\)
Vậy...
\((x-3)(x^2+3x+9)-(3x-17)=x^3-12 \)
\(pt\Leftrightarrow x^3-27-3x+17=x^3-12\)
\(\Leftrightarrow x^3-3x-10-x^3+12=0\)
\(\Leftrightarrow2-3x=0\)\(\Leftrightarrow x=\dfrac{2}{3}\)
3x + 17 = 12
3x + 17 = 12
3x = 12 - 17
3x = -5
x = -5/3
k cho tows nha
3x + 17 = 12
3x = 12 - 17
3x = -5
=> x = 1,6
| 3x + 1 | - 17 = -12
|3x + 1| - 17 = -12
=> |3x + 1| = -12 + 17
=> |3x + 1| = 5
=> 3x + 1 = 5 hoặc 3x + 1 = -5
=> 3x = 4 hoặc 3x = -6
=> x = 3/4 hoặc x = -2
vậy___
3x+1=-12 hoac 3x+1=12
3x=-12-1 3x=12-1
3x=-13 3x=11
x=-13:3 x=11:3
x=-13/3 x=11/3
vay x=-13/3 hoac 11/3
tk cho mk nha
|3x + 1 | - 17 = -12
\(|3x+1|-17=-12\)
\(\Rightarrow|3x+1|=5\)
\(\Rightarrow\orbr{\begin{cases}3x+1=5\\3x+1=-5\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}3x=4\\3x=-6\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{4}{3}\\x=-2\end{cases}}}\)
\(\left|3x+1\right|-17=-12\)
\(\Rightarrow\left|3x+1\right|=-12+17=5\)
\(\Rightarrow\orbr{\begin{cases}3x+1=5\\3x+1=-5\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}3x=4\\3x=-6\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=\frac{4}{3}\\x=-2\end{cases}}\)
Ta có :
\(|3x+1|-17=-12\)
\(\Rightarrow|3x+1|=\left(-12\right)+17\)
\(\Rightarrow|3x+1|=5\)
\(\Rightarrow\orbr{\begin{cases}3x+1=5\\3x+1=-5\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}3x=4\\3x=-6\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=4:3\\x=\left(-6\right):3\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{4}{3}\\x=-2\end{cases}}\)
Vậy x có 2 giá trị là \(\frac{4}{3};-2\)
Chúc bạn học tốt !
-17.(-3)-(x+29)=-11-3x
15-2x=-11-3x
-17-4x=-19.3-2x
46-(52-x)=12.(-7)+2x
Tìm số nguyên x, biết:
1) -16 + 23 + x = - 16
2) 2x – 35 = 15
3) 3x + 17 = 12
4) (2x – 5) + 17 = 6
5) 10 – 2(4 – 3x) = -4
6) - 12 + 3(-x + 7) = -18
Tìm số nguyên x, biết:
1) -16 + 23 + x = - 16
7+x=-16
x=-16-7
x=-23
2) 2x – 35 = 15
2x=15+35
2x=50
x=50:2
x=25
3) 3x + 17 = 12
3x=12-17
3x=-5
x=-5/3
4) (2x – 5) + 17 = 6
2x-5=6-17
2x-5=-11
2x=-11+5
2x=-6
x=-6:2
x=-3
5) 10 – 2(4 – 3x) = -4
2(4-3x)=10-(-4)
2(4-3x)=14
4-3x=14:2
4-3x=7
3x=4-7
3x=-3
x=-3:3
x=-1
6) - 12 + 3(-x + 7) = -18
3(-x+7)=-18-(-12)
3(x+7)=-6
x+7=-6:3
x+7=-2
x=-2-7
x=-9
tự đi mà làm
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(\Rightarrow x\left(x^2+3x+9\right)-3\left(x^2+3x+9\right)-3x+17=x^3-12\)
\(\Rightarrow x^3+3x^2+9x-3x^2-9x-27-3x+17=x^3-12\)
\(\Rightarrow x^3+\left(3x^2-3x^2\right)+\left(9x-9x\right)-3x-10=x^3+12\)
\(\Rightarrow x^3-3x-10=x^3+12\)
\(\Rightarrow x^3-3x-10-12=x^3\)
\(\Rightarrow x^3-3x-22=x^3\)
\(\Rightarrow3x-22=0\)
\(\Rightarrow3x=22\Rightarrow x=\dfrac{22}{3}\)