Question 211184
Let A = Aris' age now and R = Rosie's age now.
1) A = R+3 "Aris is three years older than Rosie."
2) A+7 = 2(R-5) "In seven years, Aris will be twice as old as Rosie was five years ago."
Substitute A = R+3 into equation 2) and solve for R.
(R+3)+7 = 2(R-5) Simplify.
R+10 = 2R-10 Subtract R from both sides.
10 = R-10 Add 10 to both sides.
20 = R
Rosie is 20 years old.
A = R+3
A = 23
Aris is 23 years old.