Let m = mike and t = tom
m = 5 + 2t
m + t = 65
Plug the first equation into the second equation for the m.
5 + 2t + t = 65
combine like terms
5 + 3t = 65
subtract 5 from both sides
3t = 60
divide both sides by 3
t = 20
m = 5 + 2t
m = 5 + 2(20)
m = 5 + 40
m = 45
t = 20
20 + 45 = 65 CHECKS
Answer is C. Mike is 45 years old
