Cody: 2x
Evan: x
x-7 (Evan’s age 7 years ago (-7))
2x-7( Cody’s age 7 years ago (-7))
So you add both
x-7+2x-7
And that should equal 7 (seven years ago the sum of their age was 7)
x-7+2x-7=7
3x-14=7
3x=21
x=7
Evan (x)= 7
Cody (2x)= 7 times 2
Cody= 14