SOLUTION: a certain two digit number is equal to 9 times the sum of its digits. If 63 were subtracted from the number, the digits would be reversed. Find the number.

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Question 813830: a certain two digit number is equal to 9 times the sum of its digits. If 63 were subtracted from the number, the digits would be reversed. Find the number.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
two digit number (xy) is equal to 9 times the sum of its digits.****
10x + y = 9(x+y) 0r x-8y = 0 ****
If 63 were subtracted from the number, the digits would be reversed.***
10x + y - 63 = 10y + x 0r 9x -9y = 63 0r x-y = 7
x-8y = 0
x-y = 7 |Subtracting 2nd EQ from 1st EQ
-7y = -7
y = 1 and x = 8 (x-y = 7 or x = y + 7)
Number is 81
CHECKING our Answer***
81=+9%281%2B8%29
& 81 - 63 = 18