4(-y-5)=1/2(8-4y)

Solution for 4(-y-5)=1/2(8-4y) equation:

4(-y-5)=1/2(8-4y)

We simplify the equation to the form, which is simple to understand 
4(-y-5)=1/2(8-4y)

Simplifying:
4*(-y-5)=0.5*(8-4y)

Reorder the terms in parentheses
+(-4y-20)=0.5*(8-4y)

Remove unnecessary parentheses
-4y-20=0.5+*(+8-4y+)

Reorder the terms in parentheses
-4y-20=+(+4-2y)

Remove unnecessary parentheses
-4y-20=+4-2y

We move all terms containing y to the left and all other terms to the right. 
-4y+2y=+4+20

We simplify left and right side of the equation. 
-2y=+24

We divide both sides of the equation by -2 to get y. 
y=-12