Simplify 6/9 to 2/3
2/3 = x + 2/24
Simplify 2/24 to 1/12
2/3 = x + 1/12
Subtract 1/12 from both sides
2/3 - 1/12 = x
Simplify 2/3 - 1/12 to 7/12
7/12 = x
Switch sides
x = 7/12