Question

giúp mình với mình tick đúng và theo dõi cho

Answer 1

`9,`

`a, 5/6+1/6 \div 4/3`

`= 5/6+1/8`

`= 23/24`

`b,`

`15/4*(-2/3+3/4)+15/4*(-1/3+1/4)`

`= 15/4*[(-2/3+3/4)+(-1/3+1/4)]`

`= 15/4*[(-2/3)+3/4-1/3+1/4]`

`= 15/4*[(-2/3-1/3)+(3/4+1/4)]`

`= 15/4*(-1+1)`

`= 15/4*0=0`

`10,`

`a, 35 - 3(x-30)=20`

`35- 3x-90=20`

`35+90-3x=20`

`125-3x=20`

`3x=125-20`

`3x=105`

`x=105 \div 3`

`x=35`

`b,`

`|2x-1/2|=3/2`

`=>`\(\left[{}\begin{matrix}2x-\dfrac{1}{2}=\dfrac{3}{2}\\2x-\dfrac{1}{2}=-\dfrac{3}{2}\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}2x=\dfrac{3}{2}+\dfrac{1}{2}\\2x=-\dfrac{3}{2}+\dfrac{1}{2}\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}2x=2\\2x=-1\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=1\\x=-\dfrac{1}{2}\end{matrix}\right.\)