Question 12667
16- J= 12
What your teacher meant is doing the opposite operation to get the j by itself. So lets look at the left side: 16-j; this is a positive 16, so you will nedd to add it by the opposite of +16 which is -16, so you can make that a zero. And what you do to one side you do the exact same thing to the other side.So we have:
16-j+(-16)=12-16, the 16 cancels out on the left and you are left with:
-j=-4; but we do not want to leave the j as negative, so you will divide it by  -1, and what you do to one side you do to the other. So you are left with:
j=4