Question 626975
A man is 4 times older than his son.5years ago the product of their age was 175. Find their present ages
------
Equations:
m = 4s
(m-5)(s-5) = 175
------
Substitute for "m" and solve for "s":
(4s-5)(s-5)= 175
4s^2 -25s + 25 = 175
4s^2 - 25s - 150 = 0
(x-10)(4x+15) = 0
Positive solution:
s = 10 (son's age)
m = 4s = 40 (man's age)
==========================
Cheers,
Stan H.
===============