Question 667413: john is 4 years less than twice his little brother zachs age. if the product of their ages is 126, how old is each brother? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! john is 4 years less than twice his little brother zachs age. if the product of their ages is 126, how old is each brother?
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Equations:
j = 2b-4
j*b = 126
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Substitute for "j" and solve for "b":
(2b-4)b = 126
2b^2-4b-126 = 0
b^2 - b - 63 = 0
b = 8.45.. year (brother's age)
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Solve for "j":
j = 2(8.45)-4
j = 12.9 years (john's age)
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Cheers,
Stan H.
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