1\(|0,5x|=0,5x\)
2\(|\frac{1}{3}x|=\frac{1}{3}x\)
3\(|-\frac{2}{3}|=\frac{2}{3}x\)
4\(|-\frac{1}{5}|=\frac{1}{5}x\)
\(\frac{2}{3}-1\frac{4}{15}x=\frac{-3}{5}\)
-23+0,5x=1,5
\(\frac{2}{3}-1\frac{4}{15}x=\frac{-3}{5}\)
\(1\frac{4}{15}x=\frac{19}{15}\)
\(x=1\)
- 2 3 + 0,5 x = 1,5
- 8 + 0,5 x = 1,5
0,5 x = 9,5
x = 19
tìm x:
\(\left|x\right|-5\frac{3}{7}\times\left|x\right|-\frac{3}{4}=2\times\left|x\right|+\frac{-15}{2}\)
\(50\%+\frac{2}{3}x=x+4\)
\(0,5x-\frac{2}{3}\left(x+1\right)=\frac{-1}{12}\)
\(\frac{1}{2}\left(x-\frac{2}{3}\right)-\frac{2}{5}\left(2-x\right)=\frac{1}{9}\)
tìm x:
a,\(\frac{x}{2\times5}+\frac{x}{5\times8}+\frac{x}{8\times11}+\frac{x}{11\times14}=\frac{3}{7}\)
b, \(50\%+\frac{2}{3}x=x+4\)
c,\(0,5x-\frac{2}{3}\left(x+1\right)=\frac{-1}{12}\)
d,\(\frac{1}{2}\left(x-\frac{2}{3}\right)-\frac{2}{5}\left(2-x\right)=\frac{1}{9}\)
Bài 1: Tìm x biết:
a, \(x.\cdot\left(\frac{1}{4}+\frac{1}{5}\right)-\left(\frac{1}{7}+\frac{1}{8}\right)=0\)
b, \(\left(5x-1\right).\left(2x-\frac{1}{3}\right)=0\)
c, \(\frac{3x+2}{5x+7}=\frac{3x-1}{5x+1}\)
d, \(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
e, \(\frac{-3}{4}-\left|\frac{4}{5}-x\right|=-1\)
b) \(\left(5x-1\right)\left(2x-\frac{1}{3}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}5x-1=0\\2x-\frac{1}{3}=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}5x=1\\2x=\frac{1}{3}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\frac{1}{5}\\x=\frac{1}{6}\end{matrix}\right.\)
e, \(-\frac{3}{4}-\left|\frac{4}{5}-x\right|=-1\)
\(\Leftrightarrow\left|\frac{4}{5}-x\right|=-\frac{3}{4}-\left(-1\right)\)
\(\Leftrightarrow\left|\frac{4}{5}-x\right|=\frac{1}{4}\)
\(\Leftrightarrow\left[{}\begin{matrix}\frac{4}{5}-x=\frac{1}{4}\\\frac{4}{5}-x=-\frac{1}{4}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\frac{7}{15}\\x=1,05\end{matrix}\right.\)
Vậy ....
Tìm x,biết:
a)\(\frac{4}{7}-x=\frac{1}{3}\)
b)|x-5|=7
c)\(x-\frac{2}{3}=\frac{-6}{7}\)
d)\(\frac{x}{3}=\frac{8}{12}\)
e)\(\frac{2}{3}-1\frac{4}{15}x=\frac{-3}{5}\)
f)\(-2^3+0,5x=1,5\)
g)\(2^{x-1}=16\)
Help!!
a) x=4/7 - 1/3=19/21
b) /x-5/=7 -->x-5=7 hoặc x-5=-7
--> x=12 hoặc x= -2
a,\(\frac{4}{7}-x=\frac{1}{3}\Rightarrow x=\frac{4}{7}-\frac{1}{3}\)
\(\Rightarrow x=\frac{12}{21}-\frac{7}{21}\Rightarrow x=\frac{5}{21}\)
b,\(\left|x-5\right|=7\Rightarrow\orbr{\begin{cases}x-5=7\\x-5=-7\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=12\\x=-2\end{cases}}\)
c,\(x-\frac{2}{3}=-\frac{6}{7}\Rightarrow x=-\frac{6}{7}+\frac{2}{3}\Rightarrow x=-\frac{4}{21}\)
d,\(\frac{x}{3}=\frac{8}{12}\Rightarrow x=8.3:12=2\)
e,\(\frac{2}{3}-1\frac{4}{15}x=-\frac{3}{5}\Rightarrow1\frac{4}{15}x=\frac{2}{3}+\frac{3}{5}\Rightarrow\frac{19}{15}x=\frac{19}{15}\Rightarrow x=1\)
f,\(-2^3+0,5x=1,5\Rightarrow-8+0,5x=1,5\Rightarrow0,5x=1,5+8\)
\(\Rightarrow0,5x=9,5\Rightarrow x=19\)
g,\(2^{x-1}=16\Rightarrow x-1=4\Rightarrow x=5\)
tìm x biết
a.x:15=8:24
b.36:x=54:3
c.\(3^1_2:0,4=x:1^1_7\)
d.\(\frac{1}{5}x:3=\frac{2}{3}:0,25\)
e.\(\frac{3x+2}{5x+7}=\frac{3x-1}{5x+1}\)
f.\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
Giải các phương trình sau:
a) \(\frac{2\left(x-3\right)}{4}\)- \(\frac{1}{2}\)= \(\frac{6x+9}{3}\)-2
b) \(\frac{2\left(3x+1\right)+1}{4}\)-5= \(\frac{2\left(3x-1_{ }\right)}{5}-\frac{3x+2}{10}\)
c) \(\frac{x}{3}+\frac{x-2}{4}=0,5x-2,5\)
d) \(\frac{2x-4}{3}-2x=-\frac{6x+3}{5}+\frac{1}{15}\)
giúp mình với nhé
tìm x
\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
mình viết nhầm, mình sửa lại bài nhé
\(\frac{x+1}{2x+1}-\frac{0,5x+2}{x+3}\)
\(\Rightarrow\) (x+1)(x+3) = (0,5x+2)(2x+1)
\(\Rightarrow\) x2 + 3x + x + 3 = x2 + 0,5x + 4x + 2
\(\Rightarrow\) x2 + 4x + 3 = x2 + 4,5x + 2
\(\Rightarrow\) x2 - x2 + 4x - 4,5x = 2 - 3
\(\Rightarrow\) -0,5x = -1
\(\Rightarrow\) x = \(\frac{-1}{-0,5}\)
\(\Rightarrow\) x = 2
Vậy x = 2
\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
\(\Rightarrow\) (x + 1)(x + 3) = (2x + 1)(0,5x + 2)
\(\Rightarrow\) x2 + 3x + x + 3 = x2 + 4x + 0,5x + 2
\(\Rightarrow\) x2 + 3x + x + 3 - x2 - 4x - 0,5x - 2 = 0
\(\Rightarrow\) 0,5x + 1 = 0
\(\Rightarrow\) 0,5x = 0 - 1
\(\Rightarrow\) 0,5x = -1
\(\Rightarrow\) x = -1 : 0,5
\(\Rightarrow\) x = -2
Vậy x = -2
\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+5}\)
\(\Rightarrow\) (x+1)(x+3) = (0,5x+2)(2x+1)
\(\Rightarrow\) x2 + 3x + x + 3 = x2 + 0,5x + 4x + 2
\(\Rightarrow\) x2 + 4x + 3 = x2 + 4,5x + 2
\(\Rightarrow\) x2 - x2 + 4x - 4,5x = 2 - 3
\(\Rightarrow\) -0,5x = -1
\(\Rightarrow\) x = \(\frac{-1}{-0.5}\)
\(\Rightarrow\) x =2
Vậy x = 2
Câu 3: Giải các phương trình sau bằng cách đưa về dạng ax+b=0
1. a, \(\frac{5x-2}{3}=\frac{5-3x}{2}\); b, \(\frac{10x+3}{12}=1+\frac{6+8x}{9}\)
c, \(2\left(x+\frac{3}{5}\right)=5-\left(\frac{13}{5}+x\right)\); d, \(\frac{7}{8}x-5\left(x-9\right)=\frac{20x+1,5}{6}\)
e, \(\frac{7x-1}{6}+2x=\frac{16-x}{5}\); f, 4 (0,5-1,5x)=\(\frac{5x-6}{3}\)
g, \(\frac{3x+2}{2}-\frac{3x+1}{6}=\frac{5}{3}+2x\); h, \(\frac{x+4}{5}.x+4=\frac{x}{3}-\frac{x-2}{2}\)
i, \(\frac{4x+3}{5}-\frac{6x-2}{7}=\frac{5x+4}{3}+3\); k, \(\frac{5x+2}{6}-\frac{8x-1}{3}=\frac{4x+2}{5}-5\)
m, \(\frac{2x-1}{5}-\frac{x-2}{3}=\frac{x+7}{15}\); n, \(\frac{1}{4}\left(x+3\right)=3-\frac{1}{2}\left(x+1\right).\frac{1}{3}\left(x+2\right)\)
p, \(\frac{x}{3}-\frac{2x+1}{6}=\frac{x}{6}-x\); q, \(\frac{2+x}{5}-0,5x=\frac{1-2x}{4}+0,25\)
r, \(\frac{3x-11}{11}-\frac{x}{3}=\frac{3x-5}{7}-\frac{5x-3}{9}\); s, \(\frac{9x-0,7}{4}-\frac{5x-1,5}{7}=\frac{7x-1,1}{6}-\frac{5\left(0,4-2x\right)}{6}\)
t, \(\frac{2x-8}{6}.\frac{3x+1}{4}=\frac{9x-2}{8}+\frac{3x-1}{12}\); u, \(\frac{x+5}{4}-\frac{2x-3}{3}=\frac{6x-1}{3}+\frac{2x-1}{12}\)
v, \(\frac{5x-1}{10}+\frac{2x+3}{6}=\frac{x-8}{15}-\frac{x}{30}\); w, \(\frac{2x-\frac{4-3x}{5}}{15}=\frac{7x\frac{x-3}{2}}{5}-x+1\)
Đây là những bài cơ bản mà bạn!
\(\frac{5x-2}{3}=\frac{5-3x}{2}\)
\(< =>\frac{\left(5x-2\right).2}{6}=\frac{\left(5-3x\right).3}{6}\)
\(< =>\left(5x-2\right).2=\left(5-3x\right).3\)
\(< =>10x-4=15-9x\)
\(< =>10x+9x=15+4\)
\(< =>19x=19< =>x=1\)
\(\frac{10x+3}{12}=1+\frac{6+8x}{9}\)
\(< =>\frac{\left(10x+3\right).3}{36}=\frac{36}{36}+\frac{\left(6+8x\right).4}{36}\)
\(< =>\left(10x+3\right).3=36+\left(6+8x\right).4\)
\(< =>30x+9=36+24+32x\)
\(< =>32x-30x=9-36-24\)
\(< =>2x=9-60=-51< =>x=-\frac{51}{2}\)