Jeff is 2 years younger than Carrie. 12 years agao, Carrie was twice as old as Jeff. How old is Jeff now?
Hi Jeff;
C-12=2(J-12)
C=J+2
Let's substitute...
(J+2)-12=2(J-12)
J-10=2J-24
Let's isolate J...
Let's add 10 to both sides...
10+J-10=2J-24+10
J=2J-14
Let's subtract 2J from both sides...
-2J+J=2J-14-2J
-J=-14
Jeff=14
Carrie=16
Let's check our work...
(16-12) ? 2(14-12)
4 ? 2(2)
4=4