Question 76007This question is from textbook Algebra 1
: Zelma is 18 years older than her son. She was 3 times as old as he was 1 year ago. How old are they now? This question is from textbook Algebra 1
You can put this solution on YOUR website! Let z = Zel's age now; Let s = son's age now
:
"Zelma is 18 years older than her son." says:
z = (s + 18)
or
s = (z - 18)
:
"She was 3 times as old as he was 1 year ago." says:
(z-1) = 3(s-1)
z - 1 = 3s - 3
z = 3s - 3 + 1
z = 3s - 2
:
How old are they now?
:
Substitute (z-18) for s, in z = 3s - 2
z = 3(z-18) - 2
z = 3z - 54 - 2
z - 3z = -56
-2z = -56
z = -56/-2
z = +28 yrs old; then s = 28 -18 = 10 yrs old
:
Check:
(28-1) = 3(10-1)
27 = 3(9)
