The equation is given as,
[tex]4x+2y=8[/tex]
Subtracting a positive term on both sides will not affect the equality, so we subtract '4x' both sides,
[tex]\begin{gathered} 4x+2y-4x=8-4x \\ 2y+0=8-4x \\ 2y=8-4x \end{gathered}[/tex]
Dividing both sides by a positive term will not affect the equality, so we divide both sides by '2' as,
[tex]\begin{gathered} 2y\cdot\frac{1}{2}=(8-4x)\cdot\frac{1}{2} \\ y=\frac{8}{2}-\frac{4x}{2} \\ y=4-2x \\ y=-2x+4 \end{gathered}[/tex]
Thus, the required expression is,
[tex]y=-2x+4[/tex]