For #'s 28-30 either write an equation or inequality that represents the situation. 28) Sue Ling gave her dad a $50 gift certificate. He plans to buy a $12 book on home repair and as many drill bits as he can for $1.79 each. 29) A chess club has 500 members but is losing 30 members each year. A computer club has 130 members and is gaining 20 members per year. Write an equation that could be used to find out when both clubs have the same number of members.
30) Gayle and Ernie are going to sell canvas backpacks. They spend $75 for a used sewing machine and estimate the canvas will cost $15 per backpack. They plan to sell the backpacks for $30. Write an inequality to find when they will start making a profit.​