Đáp án + Giải thích các bước giải:
`a)` `1/4+1/3:(2x-1)=-5`
`=>1/3:(2x-1)=-5-1/4`
`=>1/3:(2x-1)=-21/4`
`=>2x-1=1/3:(-21/4)`
`=>2x-1=1/3*(-4/21)`
`=>2x-1=-4/63`
`=>2x=-4/63+1=59/63`
`=>x=59/63:2=59/126`
Vậy `x = 59/126`
`b)` `(3x-1)(-1/2x-5)=0`
`=>`\(\left[ \begin{array}{l}3x-1=0\\-\dfrac{1}{2}x-5=0\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}x=\dfrac{1}{3}\\x=-10\end{array} \right.\)
Vậy `x in {1/3;-10}`
`c)` `-5(x+1/5)-1/2(x-2/6)=3/2x-5/6`
`=>-5x-1-1/2x+1/6-3/2x+5/6=0`
`=>(-5-1/2-3/2)x+(-1+1/6+5/6)=0`
`=>-7x=0=>x=0`
Vậy `x = 0`
`d)` `17/2-|2x-3/4|=-7/4`
`=>|2x-3/4|=17/2-(-7/4)`
`=>|2x-3/4|=17/2+7/4`
`=>|2x-3/4|=34/4+7/4=41/4`
`=>`\(\left[ \begin{array}{l}2x-\dfrac{3}{4}=\dfrac{41}{4}\\2x-\dfrac{3}{4}=-\dfrac{41}{4}\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}2x=11\\2x=-\dfrac{19}{2}\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x=\dfrac{11}{2}\\x=-\dfrac{19}{4}\end{array} \right.\)
Vậy `x in {11/2;-19/4}`.
