1. Assignment, pencil, red pen, highlighter, calculator The Key Ring Store has figured out that if they sell zero “Mr. T. In Your Pocket” key chains, then they make no profit. Likewise, if they make 200 key chains, they make no profit. They also figured out that their maximum profit would be $500. Their situation can be modeled by the graph of a parabola. a) Make and label a graph modeling profit vs. production. b) Write an equation that models their situation. c) How much profit will 40 key chains produce? total:

2. 200 0 $500 100 (100, 500) profit $ # of key chains y = a(x – h) 2 + k y = a(x – 100) 2 + 500 –500 –500 = 10000a 10000 0 = a(0 – 100) 2 + 500 0 = a( – 100) 2 + 500 0 = 10000a + 500 a) Make and label a graph modeling profit vs. production. b) Write an equation that models their situation. c) How much profit will 40 key chains produce? +1 x–axis total: +1 y–axis +1 parabola +1 +2 y x 0

3. Get together with some classmates and complete the STT. It is time for the…