Đáp án:
`c) y=\frac{1}{2}`
`d)\(\left[ \begin{array}{l}y=-8\\y=10\end{array} \right.\)
`h) \(\left[ \begin{array}{l}y=0\\y=\frac{11}{2}\end{array} \right.\)
`i)y=-1`
Giải thích các bước giải:
`c)4y^2+1=4y`
`⇔4y^2+1-4y=0`
`⇔4y^2-4y+1=0`
`⇔(2y-1)^2=0`
`⇔2y-1=0`
`⇔y=\frac{1}{2}`
`d)y^2-2y=80`
`⇔y^2-2y-80=0`
`⇔y^2+8y-10y-80=0`
`⇔y(y+8)-10(y+8)=0`
`⇔(y+8)(y-10)=0`
`⇔`\(\left[ \begin{array}{l}y=-8\\y=10\end{array} \right.\)
`i) (2y-3)(y+1)+y(y-2)=3(y+2)^2`
`⇔2y^2+2y-3y-3+y^2-2y=3(y^2+4y+4)`
`⇔3y^2-3y-3=3y^2+12y+12`
`⇔-3y-3=12y+12`
`⇔-3y-12y=12+3`
`⇔-15y=15`
`⇔y=-1`
`h)2y^2-11y=0`
`⇔y(2y-11)=0`
`⇔\(\left[ \begin{array}{l}y=0\\y=\frac{11}{2}\end{array} \right.\)
