Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a,3x-0,75=-1,2
3x=-1,2+-0,75
3x=-9/20
x=-9/20:3
x=-3/20
kl:....
b,2/3/5:(2x-1/2)=1,3
2/3/5??????
c,3/4x-5/6=7/12x-5/4
3/4x-7/12x=-5/4+5/6
9/12x-7/12x=-15/12+10/12
2/12x=-5/12
2:12x=-5/12
12x=2:-5/12
12x=-24/5
x=-24/5:12
x=-2/5
kl:....
chúc bn học tốt
CÂU 10:
a, -x - 84 + 214 = -16 b, 2x -15 = 40 - ( 3x +10 )
x = - ( -16 -214 + 84 ) 2x + 3x = 40 -10 +15
x = 16 + 214 - 84 5x = 45
x = 146 x = 9
c, \(|-x-2|-5=3\) d, ( x - 2)(2x + 1) = 0
\(|-x-2|=8\) => x - 2 = 0 hoặc 2x + 1 = 0
=> - x - 2 = 8 hoặc x + 2 = 8 \(\orbr{\begin{cases}x-2=0\\2x+1=0\end{cases}=>}\orbr{\begin{cases}x=2\\x=-\frac{1}{2}\end{cases}}\)
\(\orbr{\begin{cases}-x-2=8\\x+2=8\end{cases}=>\orbr{\begin{cases}x=-10\\x=6\end{cases}}}\)
a; \(\dfrac{93}{17}\): \(x\) + (- \(\dfrac{21}{17}\)) : \(x\) + \(\dfrac{22}{7}\): \(\dfrac{22}{3}\) = \(\dfrac{5}{14}\)
\(\dfrac{94}{17}\) \(\times\) \(\dfrac{1}{x}\) - \(\dfrac{21}{17}\) \(\times\) \(\dfrac{1}{x}\) + \(\dfrac{3}{7}\) = \(\dfrac{5}{14}\)
\(\dfrac{72}{17}\) \(\times\) \(\dfrac{1}{x}\) + \(\dfrac{3}{7}\) = \(\dfrac{5}{14}\)
\(\dfrac{72}{17x}\) = \(\dfrac{5}{14}\) - \(\dfrac{3}{7}\)
\(\dfrac{72}{17x}\) = - \(\dfrac{1}{14}\)
17\(x\) = 72.(-14)
17\(x\) = - 1008
\(x\) = - 1008 : 17
\(x\) = - \(\dfrac{1008}{17}\)
Vậy \(x\) \(=-\dfrac{1008}{17}\)
b; - \(\dfrac{32}{27}\) - (3\(x\) - \(\dfrac{7}{9}\))3 = - \(\dfrac{24}{27}\)
- \(\dfrac{32}{27}\) + \(\dfrac{24}{27}\) = (3\(x\) - \(\dfrac{7}{9}\))3
(3\(x-\dfrac{7}{9}\))3 = - \(\dfrac{8}{27}\)
(3\(x-\dfrac{7}{9}\))3 = (- \(\dfrac{2}{3}\))3
3\(x-\dfrac{7}{9}\) = - \(\dfrac{2}{3}\)
3\(x\) = - \(\dfrac{2}{3}\) + \(\dfrac{7}{9}\)
3\(x\) = \(\dfrac{1}{9}\)
\(x\) = \(\dfrac{1}{9}\) : 3
\(x\) = \(\dfrac{1}{27}\)
Vậy \(x=\dfrac{1}{27}\)
3 . x + 25% . x = -0,75
3 . x + 0,25 . x = -0,75
x . ( 3 + 0,25 ) = -0,75
x . 3,25 = -0,75
x = -0,75 : 3,25
x = \(-\frac{3}{13}\)
\(a,\left[0,75x+\frac{5}{2}\right]-\frac{4}{7}-\left[-\frac{1}{3}\right]=-\frac{5}{6}\)
\(\Leftrightarrow\left[0,75x+\frac{5}{2}\right]-\frac{4}{7}+\frac{1}{3}=-\frac{5}{6}\)
\(\Leftrightarrow\left[0,75x+\frac{5}{2}\right]=-\frac{5}{6}-\frac{1}{3}+\frac{4}{7}\)
\(\Leftrightarrow0,75x+\frac{5}{2}=-\frac{25}{42}\)
\(\Leftrightarrow0,75x=-\frac{65}{21}\Leftrightarrow x=-\frac{260}{63}\)
\(b,\left[4x-9\right]\left[2,5+-\frac{7}{3}x\right]=0\)
\(\Leftrightarrow\orbr{\begin{cases}4x-9=0\\2,5+-\frac{7}{3}x=0\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{9}{4}\\x=\frac{15}{14}\end{cases}}\)
Vậy \(x\in\left\{\frac{9}{4};\frac{15}{14}\right\}\)
Tham khảo nhé phamthiminhanh
x +3x :2 =0,75
=>x +1,5x = 0,75
=>(1+1,5)x = 0,75
=>2,5x =0,75
=>x =0,3
(x + 3x) : 2 = 0,75
=> 4x = 0.75 . 2
=> 4x = 1,5
=> x = 1,5 : 4