SOLUTION: In What postive base b does the equation 4*12=103 for multiplaction of base b hold?

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Question 30430: In What postive base b does the equation 4*12=103 for multiplaction of base b hold?
Answer by Fermat(136) About Me  (Show Source):
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Let the base be b.
the numbers in the expression can be re-written as,
4+=+4%2Ab%5E0
12+=+1%2Ab%5E1+%2B+2%2Ab%5E0
103+=+1%2Ab%5E2+%2B+0%2Ab%5E1+%2B+3%2Ab%5E0
or,
4 = 4
12 = b + 2
103 = bē + 3
Therefore,
4*(b+2) = (bē+3)
4b + 8 = bē + 3
bē - 4b - 5 = 0
(b+1)(b-5) = 0
b = -1, b = 5
since the base is to be positivee, then
Ans: b = 5
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