Question

The value of a two-digit number is twice as large as the sum of its digits. If the digits are reversed, the resulting number would be 9 less than 5 times the original number. Find the original number.

Answer 1

The value of a two digit number is twice as large as the sum of its digits. If the digits were reversed, the resulting number would be 9 less than 5 times the original number. Find the original number.
t = tens digit
u = units digit
10t+u = original number
10u+t = the number named when the digits were reversed
10u+t = 9-5(10t+u)
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EQUATION:
10t + u = 2(t + u)
10u + t = 5(10t+u)-9
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Rearrange the equations:
8t -u = 0


49t - 5u = 9
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solve by substitution:
49t - 5(8t) = 9
9t = 9
t = 1
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Substitute to solve for "u":
u = 8t so u = 8
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Original Number 18
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Answer 2

you are amazing and u do it exactly the way I do u get a medal and are a fav!!!

Answer 3

Thanks @Boyce Glad I could help! :-)

Answer 4

How old are u? I am almost 16.