Question 170691
lets call the 10 digit number a and the ones digit number b.
:
remember a two digit number take 35 for instance can be written as 3(10)+5(1)
with that in mind lets write and equation based on that understanding.
:
10(a)+1(b)=(10(b)+1(a))+9--->9a-9b=9--->a-b=1....eq 1
a+b=11.................................eq 2
:
add the 2 equations together to eliminate the b term.
:
2a=12
:
{{{highlight(a=6)}}}
{{{highlight(b=11-(6)=5)}}}