a)Viết dưới dạng phân số rồi sử dụng tích chéo ý
b)\(\frac{-1}{7}.2^3-2x:1\frac{4}{3}=-2^{x-1}\)
\(\Rightarrow\frac{-8}{7}-2x:\frac{7}{3}=-2^{x-1}\)
\(\Rightarrow\frac{-8}{7}-\frac{6x}{7}=-2^{x-1}\)
\(\Rightarrow\frac{-8-6x}{7}=\frac{2^{x-1}}{-1}\)
\(\Rightarrow-1\left(-8-6x\right)=7.2^{x-1}\)
\(\Rightarrow6x+8=7.2^{x-1}\)
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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, \(\frac{-3}{4}-\left|\frac{4}{5}-x\right|=-1\)
tìm x biết
a.\(\frac{-3}{4}-\left|\frac{4}{5}-x\right|=-1\)
b.\(\left|\frac{-1}{2}-x\right|=\frac{1}{3}\)
c.\(\left|2^1_2+x\right|-\frac{-2}{3}=3\)
d.\(\frac{-5}{7}-\left|\frac{1}{2}-x\right|=\frac{-11}{4}\)
e.\(\left|3x+4\right|=2\left|2x-9\right|\)
Bài 1: Tìm x:
a) \(\frac{6x+5}{2}-\left(2x+\frac{2x+1}{2}\right)=\frac{10x+3}{4}\)
b) \(\frac{3.\left(2x+1\right)}{4}-\frac{5x+3}{6}+\frac{x+1}{3}=x+\frac{7}{12}\)
GIÚP MIK NHA!! MIK ĐAG CẦN GẤP
Tìm x, biết
a) \(\frac{3}{2}x-\frac{7}{3}=-\frac{1}{4}\)
b) \(\frac{3}{4}-\left(x+\frac{1}{2}\right)=\frac{1}{4}\)
c) \(\left|2x-1\right|-\frac{1}{2}=\frac{1}{3}\)
tìm x biết
a) \(\frac{x-1}{x+2}=\frac{4}{5}\left(x\ne-2\right)\) b)22x+1+4x+3=264 c)\(\frac{x^2}{-8}=\frac{27}{x}\left(x\ne0\right)\) d)\(\frac{x+7}{-20}=\frac{-5}{x+7}\left(x\ne-7\right)\) e)\(\frac{x}{-8}=\frac{2}{-x^3}\left(x\ne0\right)\)
tìm x , y , z biết
a, 3x=4y , 3y =5z và x - y - z=1
b, \(\frac{x}{2}=\frac{y}{7}=\frac{5}{z}\) và yz - xy - z2 = 72
c, \(\frac{x}{2}=\frac{y}{7}=\frac{z}{8}\) và 2x2 + xy - xz = 54
d, \(\frac{x+3}{5}=\frac{y-4}{3}=\frac{z-5}{2}\) và 2x - 3y - z = -26
a)Cho \(\frac{3x-2y}{4}=\frac{2z-4x}{3}=\frac{4y-3z}{2}\)và 3x-2y+z=40.Tìm x,y,z
b)Tìm x,y biết \(\frac{2x+1}{5}=\frac{3y-2}{7}=\frac{2x+3y-1}{6x}\)
Giúp mik với!help me~~~
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.\(\frac{x+1}{2x+1}=\frac{0,5x+2}{x+3}\)
1.tìm x
a.\(\frac{-5}{8}+x=\frac{4}{9}\)
b.\(1^3_4.x+1^1_2=-\frac{4}{5}\)
c.\(\frac{1}{4}+\frac{3}{4}x=\frac{3}{4}\)
d.\(x.\left(\frac{1}{4}+\frac{1}{5}\right)-\left(\frac{1}{7}+\frac{1}{8}\right)=0\)
e.\(\frac{3}{35}-\left(\frac{3}{5}+x\right)=\frac{2}{7}\)
f.\(\frac{3}{7}+\frac{1}{7}:x=\frac{3}{14}\)
g.\(\left(5x-1\right)\left(2x-\frac{1}{3}\right)=0\)