Giải thích các bước giải:
a)`(2x+1)^2=16/25`
`(2x+1)^2=(4/5)^2=(-4/5)^2`
`=>`\(\left[ \begin{array}{l}2x+1=\frac{4}{5}\\2x+1=\frac{-4}{5}\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}2x+1=0,8\\2x+1=-0,8\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}2x=0,8-1\\2x=-0,8-1\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}2x=0,2\\2x=-1,8\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}2x=0,2:2\\x=(-1,8):2\end{array} \right.\)
`=>`\(\left[ \begin{array}{l}x=0,1\\x=-0,9\end{array} \right.\)
Vậy `x in{0,1;-0,9}`
`b)1/3+1/2:x=1/5`
`1/2:x=1/5-1/3`
`1/2:x=3/15-5/15`
`1/2:x=-2/15`
`x=1/2:-2/15`
`x=1/2. -15/2`
`x=-15/4`
Vậy `x=-15/4`
