Cary is 7 years older than Dan. In 7 years the sum of their ages will be 79. Find the age of each man now.

Dan is 29. Cary is 36.

Step-by-step explanation:

Let Dan's age now be D.

Let Cary's age now be C.

"Cary is 7 years older than Dan."

C = D + 7

"In 7 years the sum of their ages will be 79. "

In 7 years, the ages of Dan and Cary will be D + 7 and C + 7, respectively.

D + 7 + C + 7 = 79

C + D + 14 = 79

C + D = 65

C = D + 7

The last two equations in bold above form a system of equations. Since the second equation is already solved for C, we use the substitution method.

D + 7 + D = 65

2D + 7 = 65

2D = 58

D = 29

C = D + 7

C = 29 + 7

C = 36

Answer: Dan is 29. Cary is 36.