Question 760616
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
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