First, we need to isolate the #g# term on the left side of the inequality by subtracting #color(red)(12)# from each side of the inequality which will also maintain the balance of the inequality.
#12 - color(red)(12) - 2/3g < 24 - color(red)(12)#
#0 - 2/3g < 12#
#-2/3g < 12#
Now we need to multiply each side of the inequalty by the inverse of the #g# coefficient which is #color(blue)(-3/2)#,
However, because we are working with an inequality, whenever you multiply or divide an inequality by a negative number the rule is to reverse the inequality.
#color(blue)(-3/2) xx -2/3g color(red)(>) color(blue)(-3/2) xx 12#
#-cancel(color(blue)(3))/cancel(color(blue)(2)) xx -color(blue)(cancel(color(black)(2)))/color(blue)(cancel(color(black)(3)))g color(red)(>) -36/2#
#g > -18#
