Question

sum of the digits of a 2-digit number is 8.If 18 is added to the number ,the digits change their places .Find the number in a small formula.

Answer 1

x+y = 8
10x+y+18 = 10y+x
9x + 18 = 9y
x+2=y
x+x+2=8
2x=6
x=3
y=x+2
y=5
no. is = 35