Respuesta :

irspow
c=2 and j=4

j+y=2(c+y)-7

j+y=2c+2y-7  and since j=4 and c=2 we have:

4+y=2*2+2y-7

y+4=2y+4-7

y+4=2y-3

-y+4=-3

-y=-7

y=7

So in 7 years Jenny will be 7 years younger than twice Chris' age.

check...

4+7=2(2+7)-7

11=2(9)-7

11=18-7

11=11
Let's write out all the possibilities. 

2, 3, 4, 5, 6, 7,  8,   9,  10, 11, 12, 13
4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15

The correct answer is 7 years.

Hope this helped! Comment or DM me if you have any more questions. :)