Question 1022105
The idea is to get y by itself.
What we need to do then is to get rid of everything on the same side as the y.
Do you see how 4 is being added to the y?
To undo adding by 4, we need to subtract 4.
But whatever we do to one side, we MUST do to the other side, so we get
y + 4 = -1
y + 4 - 4 = -1 - 4
Now plus four and minus four cancel each other (it's what we wanted), and we get
y = -5
and we are done.
Did that help at all?