`#N`
`a,`
`x-3/4=2/7`
`x=2/7+3/4`
`x=29/28`
`b,`
`1/20-(x-8/5)=1/10`
`x-8/5=1/20-1/10`
`x-8/5=-1/20`
`x=(-1/20)+8/5`
`x=31/20`
`c,`
`|2x-1|=1/2`
`=>`\(\left[{}\begin{matrix}2x-1=\dfrac{1}{2}\\2x-1=-\dfrac{1}{2}\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}2x=\dfrac{1}{2}+1\\2x=-\dfrac{1}{2}+1\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}2x=\dfrac{3}{2}\\2x=\dfrac{1}{2}\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=\dfrac{3}{2}\div2\\x=\dfrac{1}{2}\div2\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=\dfrac{1}{4}\end{matrix}\right.\)
`d,`
`3/5+4/9 \div x=2/3`
`4/9 \div x=2/3 -3/5`
`4/9 \div x=1/15`
`x=4/9 \div 1/15`
`x=20/3`
`e,`
`2/3(x-1/2)=4/3`
`x-1/2=4/3 \div 2/3`
`x-1/2=2`
`x=2+1/2`
`x=5/2`
`f,` Kết quả của biểu thức là gì v ạ ;-;?
`g,`\(\left|x-\dfrac{1}{3}\right|-\sqrt{\dfrac{1}{16}}=\sqrt{\dfrac{1}{9}}\)
\(\left|x-\dfrac{1}{3}\right|=\sqrt{\dfrac{1}{9}}-\sqrt{\dfrac{1}{16}}\)
\(\left|x-\dfrac{1}{3}\right|=\dfrac{1}{3}-\dfrac{1}{4}\)
\(\left|x-\dfrac{1}{3}\right|=\dfrac{1}{12}\)
\(\Rightarrow\left[{}\begin{matrix}x-\dfrac{1}{3}=\dfrac{1}{12}\\x-\dfrac{1}{3}=-\dfrac{1}{12}\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=\dfrac{1}{12}+\dfrac{1}{3}\\x=-\dfrac{1}{12}+\dfrac{1}{3}\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\dfrac{5}{12}\\x=\dfrac{1}{4}\end{matrix}\right.\)
`h,`
`(x+1)^2=49*2+2`
`(x+1)^2=98+2`
`(x+1)^2=100`
`(x+1)^2=(+-10)^2`
`->`\(\left[{}\begin{matrix}x+1=10\\x+1=-10\end{matrix}\right.\)
`=>`\(\left[{}\begin{matrix}x=10-1\\x=-10-1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=9\\x=-11\end{matrix}\right.\)
`i,`
\(3^x+3^{x+1}=108\)
`3^x+3^x*3=108`
`3^x(1+3)=108`
`3^x*4=108`
`3^x=108 \div 4`
`3^x=27`
`3^x=3^3`
`-> x=3`
a: x=2/7+3/4=29/28
b: =>x-8/5=-1/20
=>x=31/20
c: =>2x-1=1/2 hoặc 2x-1=-1/2
=>2x=3/2 hoặc 2x=1/2
=>x=1/4 hoặc x=3/4
d: =>4/9:x=2/3-3/5=1/15
=>x=20/3
e: =>x-1/2=2
=>x=5/2
f: =>x-3/5=0 hoặc 3-x=0
=>x=3 hoặc x=3/5
h: =>(x+1)^2=100
=>x+1=10 hoặc x+1=-10
=>x=-11 hoặc x=9
i: =>3^x*4=108
=>3^x=27
=>x=3
