Zero product says that if you have x=0, then the non-zero factors equal zero
so try to move all to one side to get it to equal zero and factor
4y^3-4=y-16y^2 add 16y^2 to both sides 4y^3+16y^2-4=y subtract y 4y^3+16y^2-y-4=0 gropu and factor (4y^3+16y^2)+(-y-4)=0 (4y^2)(y+4)+(-1)(y+4)=0 reverse distribute ba+ca=a(b+c) (4y^2-1)(y+4)=0 set each to zero
4y^2-1=0 add 1 4y^2=1 divide by 4 y^2=1/4 square root both sides y=+/-1/2