SOLUTION: I am so stuck! How do I solve using two equations with two variables? The tens digit of a two-digit number is twice the units digit. If the digits are reversed, the new number

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Question 141500This question is from textbook Prentice hall algebra 1
: I am so stuck! How do I solve using two equations with two variables?
The tens digit of a two-digit number is twice the units digit. If the digits are reversed, the new number is 36 less than the original number. Find the number. This question is from textbook Prentice hall algebra 1

Answer by solver91311(24713) About Me  (Show Source):
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Let x be the tens digit.
Let y be the ones digit.

The number is then 10x+%2B+y
(if x were 6 and y were 3, then the number would be 63 which is 10%286%29%2B3)

and we know that x+=+2y

The new number with the digits reversed must be 10y%2Bx and this is 36 less than the original number, so:

10x%2By-36=10y%2Bx. To solve, substitute 2y for x because x=2y, and then solve for y, multiply by 2 to get x, and then construct the number.

Remember to check your work by constructing the number, reversing the digits, and then subtracting to make sure you get 36.