Andrew M. answered 03/12/18
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
Let p = Phil's current age
Let t = Tim's current age
In 4 years Phil will be p+4 years old and Tim will be t+4 years old
2 years ago Phil was p-2 years old and Tim was t-2 years old
In 4 years, Phil will be half Tim's age:
p+4 = (1/2)(t+4)
2p + 8 = t + 4
2p - t = -4 {equation 1}
Two years ago, Tim was 5 times Phil's age:
t - 2 = 5(p-2)
t - 2 = 5p - 10
-5p + t = -8 {equation 2}
Add the two equations to eliminate t and solve for p
2p - t = -4
-5p+t = -8
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-3p = -12
p = 4
Phil is 4 years old
Substitute the value 4 for p in either equation 1 or equation 2 to find Tim's current age