3x-18 is less than -90 First, you add 18 to both sides of the inequality (getting 3x is less than -72). Then you divide by 3 on both sides giving you your answer x is less than -24
X is greater than 36. to find this you substraction 18 from both sides which leaves you with -3x<-108 then you divide both sides by -3 and when working with inequalities you have to flip the sign whenever you multiply or divide by a negative. so you end up with x>36