6/(y-4)-y/(y+2)= 6/(y-4) . y/(y+2) khó quá giúp mik nhanh nha

`6/(y-4)-y/(y+2)= 6/(y-4) . y/(y+2)`

ĐKXĐ : `x \ne 4 , x \ne -2`

`⇔ (6(y+2)-y(y-4))/((y+2)(y-4)) = (6y)/((y-4)(y+2))`

`⇔ 6(y+2)-y(y-4) = 6y`

`⇔ -y^2 + 10y + 12 = 6y`

`⇔ -y^2 + 4y + 12 = 0`

`⇔ -(y+2)(y-6)=0`

`⇔`\(\left[ \begin{array}{l}y+2=0\\y-6=0\end{array} \right.\) 

`⇔`\(\left[ \begin{array}{l}y=-2\text{(loại)}\\y=6\text{(thỏa mãn)}\end{array} \right.\) 

Vậy `y = 6`