Question

Find all digits x and y such that 6xx(bar on top) − 1y8(bar on top) = 47y(bar on top). (As usual, 6xx(bar on top) is the 3-digit number with 6 in the hundreds place, x in the tens place, and x in the ones place, etc.)

Answer 1

\[6xx - 1y8 = 47y\]

Answer 2

expand it and see if you can get an useful relation between x and y

Answer 3

\[(600+10x+x) - (100+10y+8) = (400+70+y)\]

simplify