Question

The sum of the two digit number is 9.if 9 is added to the number formed by reversing the digit then the result is thrice the original number.Find the original number.

Answer 1

10x+y=9
x+10y+9=3(10x+y)
x+10y+9=30x+3y
x-30x+10y-3y=-9
-29x+7y=-9