SOLUTION: A's age is two years less than three times that of B. Eight years ago the sum of their ages was 42. How old is A?

Algebra.Com
Question 668766: A's age is two years less than three times that of B. Eight years ago the sum of their ages was 42. How old is A?
Answer by amazingrace333(11)   (Show Source): You can put this solution on YOUR website!
So we know that A's age = 3 times B's age - 2 years or
A = 3B - 2
and
A's age minus 8 yrs + B's age minus 8 yrs = 42 or
A-8 + B-8 = 42
Simplify and solve for only one variable:
A + (-8) + B + (-8) = 42
Combine likes:
A + B + (-16) = 42
Simplify:
A + B = 42 + 16
A + B = 58
A = 58 - B
Substitute 58-B for A in our original equation and solve:
58-B = 3B-2
58 - B + 2 = 3B - 2 + 2
60 - B = 3B
60 -B +B = 3B + B
60 = 4B
60/4 = 4B/4
15 = B
Therefore, A = 58 - 15 or 43
Check your answer:
A's age of 43 = 3 x B's age -2 yrs or 3(15)-2 or 45-2 which is 43
So, A is 43 years old and B is 15 years old.

RELATED QUESTIONS

The sum of the ages of a couple is 60. In eight years, husband's age will be five years... (answered by stanbon)
A man is three times as old as his son. Eight years ago the sum of their ages was 36.... (answered by vleith)
Pikachu is three times as old as a quarter of charizards age. Seven years ago the sum of... (answered by josgarithmetic)
Two times the mother’s age is four more than eight times her daughter’s age. Five... (answered by josgarithmetic,ikleyn)
1. If Samantha were three times as old as she was five years ago, she will be sixty less... (answered by josmiceli)
A father is 3 times as old as his son, eight years ago the father's age was 5 times that... (answered by hamsanash1981@gmail.com)
a father is now threes times as old as his son. Eight years ago the father's age was five (answered by ewatrrr)
The sum of the ages of two sisters, Mary and Jane, is 24 years. Four years ago three... (answered by josgarithmetic,MathTherapy)
The sum of the ages of two sisters, Mary and Jane, is 24 years. Four years ago three... (answered by josgarithmetic)