SOLUTION: A man is 3 times as old as his daughter, 8 years ago the product of their ages is 112, find their present ages

Question 760616: A man is 3 times as old as his daughter, 8 years ago the product of their ages is 112, find their present ages
Found 2 solutions by unlockmath, tommyt3rd:
Answer by unlockmath(1688) (Show Source): You can put this solution on YOUR website!
Hello,
Good problem.
Setting up the 2 equations correctly is the key. Let "m" represent man and "d" for daughter:
m=3d
(m-8)(d-8)=112
Substitute to get:
(3d-8)(d-8)=112
Expand out to:
3d^2-32d+64=112
Rewritten as:
3d^2-32d-48=0
Use quadratic Formula and we get:
d=12
So the father is 36 years old.
Make sense?
RJ
www.math-unlock.com
Answer by tommyt3rd(5050) (Show Source): You can put this solution on YOUR website!
Notice:
Factors of 112 are
1, 112
2, 56
4, 28 <--- most likely ages 8 years ago!
7, 16
8, 14

Now we verify...
3(4+8)=36=28+8

so their ages are 12 and 36
RELATED QUESTIONS
A lady is three times as old as her daughter. 8 years ago the product of their ages was... (answered by solver91311,stanbon)
A man is now five times as old as his daughter and five years ago the product of their... (answered by ikleyn)
A man is 3 times as old as his son. 8 years ago the product of their age was 112. Find... (answered by mananth,Maths68)
please help me solve a woman is 3 times as old as her son. 8 years ago the product of... (answered by greenestamps)
A woman is 3 times as old as her son. 8 years ago the product of their ages was 112. Find (answered by ikleyn,MathLover1)
A man is now 5 times as old as his son, four years ago the product of their ages was 52.... (answered by Cromlix)
a man is now 5 times as old as his son . Four years ago, the product of their ages was... (answered by LinnW)
A MAN IS 3 TIMES AS OLD AS HIS SON,4 YEARS AGO,THE SUM OF THEIR AGES WAS 24.FIND THEIR... (answered by pj66)
A man is three times as old as his son and six years ago the product of their age was... (answered by ptaylor)