Hey there! I'm happy to help!
Let's represent Ben's age with a B and Jeff's with a J in a few equations below.
B=J-9 (Ben is 9 years younger than Jeff)
B+10+J+10=67 (In 10 years, the sum of their ages will be 67)
We know that B is equal to J-9. So, in the second equation, we can replace B with J-9 to solve for J.
J-9+10+J+10=67
We combine like terms.
2J+11=67
We subtract 11 from both sides.
2J=56
We divide both sides by two.
J=28
And, we know that Ben is nine years younger than Jeff, so this means Ben is 19 years old.
Ben is 19 years old and Jeff is 28.
I hope that this helps! Have a wonderful day! :D
