First, multiply each side of the equation by color(red)(18) to eliminate the fractions while keeping the equation balanced. Eliminating the fractions up front will make the problem easier to work with and color(red)(18) is the least common denominator of the two fractions:
color(red)(18)((7/9)x - 1/2) = color(red)(18) xx 3
(color(red)(18) xx (7/9)x) - (color(red)(18) xx 1/2) = 54
(cancel(color(red)(18))2 xx (7/color(red)(cancel(color(black)(9))))x) - (cancel(color(red)(18))9 xx 1/color(red)(cancel(color(black)(2)))) = 54
14x - 9 = 54
Next, add color(red)(9) to each side of the equation to isolate the x term while keeping the equation balanced:
14x - 9 + color(red)(9) = 54 + color(red)(9)
14x - 0 = 63
14x = 63
Now, divide each side of the equation by color(red)(14) to solve for x while keeping the equation balanced:
(14x)/color(red)(14) = 63/color(red)(14)
(color(red)(cancel(color(black)(14)))x)/cancel(color(red)(14)) = (7 xx 9)/(7 xx 2)
x = (color(red)(cancel(color(black)(7))) xx 9)/(color(red)(cancel(color(black)(7))) xx 2)
x = 9/2