Posted by **tonya** on Friday, September 1, 2006 at 6:17pm.

4(j)-7=9

Add 7 to both sides of the equation and you get

4 j = 16

Now divide both sides of the equation by 4 and you will find out what the value of j is.

Whenever you perform the same mathematical operation on both sides of an equation, you end up with another equation that is valid.