SOLUTION: The units digit of a two-digit number is 2 more than twice the tens digit. When the digits are reversed, the difference of it to the original number is 31 less than twice the origi

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Question 1201465: The units digit of a two-digit number is 2 more than twice the tens digit. When the digits are reversed, the difference of it to the original number is 31 less than twice the original number. Find the original number.
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
u and t
Ones and Tens
10t%2Bu, the original number

u=2t%2B2

Reversing the number, t%2B10u

%28t%2B10u%29-%2810t%2Bu%29=2%2810t%2Bu%29-31, second part of description

9u-9t=20t%2B2u-31
7u-29t=-31
29t-7u=31
-
Substituting for u
29t-7%282t%2B2%29=31
29t-14t-14=31
15t=31%2B14
15t=45
highlight%28t=3%29
-
substituting into u
u=2%2A3%2B2
highlight%28u=8%29

Original Number, 38