Question

y-16-3y=0

Answer 1

y-16-3y=0
combine like expressions (y&-3y)
-2y-16=0
add 16 to the other side
-2y=16
divide each side by -2 to get y by itself
y=-8
plug back into your original problem to see if it is correct:)
y-16-3y=0
-8-16-3(-8)=0
0=0
Y=-8