Equation to Model Situation

Bob has $150 in his savings account and saves $40 per month.  Which equation represents the amount Bob has in his account after x months?

• y = 150 + 40

• y = 40x + 150

• y = 150x + 40

A holiday meal costs $12.50 a person plus a delivery fee of $30.  Which equation represents the amount a holiday meal costs, including delivery, for x people?

• y = 30 + 12.5x 

• y = 12.5 + 30

• y = 12.5 + 30x

Easy Car Rental charges $8.50 an hour plus a rental fee of $25.50. Which equation represents the total charges for x hours?

• y = 8.5 + 25.5

• y = 25.5 + 8.5x

• y = 8.5 + 25.5x

A tennis tournament begins with 128 players. At the end of round one, there will be 64 players. There are 32 players at the end of round 2 and 16 players remaining after round 3. Write the equation that best models this situation.

• y = -64x + 128

• y = 0.5x + 128

• y = 128(0.5)^x

• y = 128(2)^x

Write an exponential function to model the situation. The cost of tuition at a college is $12,000 and is increasing at a rate of 6% per year.

• C(t) = 12000(.94)^t

• C(t) = 12000(1.94)^t

• C(t) = 12000(.06)^t

• C(t) = 12000(1.06)^t

The function y = 24,220 (0.85)^x represents Mr. Bittle's investment in the stock exchange where x is measured in months.

Which statement is NOT true.

• Mr. Bittle loses 85% of his investment monthly

• Mr. Bittle initially invested $24,220

• Each month Mr. Bittle loses 15% of his investment

Write an exponential function to model the situation. You invest $1500. Your investment escalates at a rate of 3.5%.

• B(t) = 1500(0.965)^t

• B(t) = 1500(1.035)^t

• B(t) = 1500(.035)^t

• B(t) = 1500(1.965)^t

At American Eagle, it costs $15 for each t-shirt you buy. Write an equation to model this situation.

• y = 15x+20

• y = 20x

• y = 15x

• y = 15x-20

Mr. Bates doesn't have Amazon Prime. He wants to buy DVDs for his parents that cost cost $3 each. There is a $7 shipping fee for the entire order. Write an equation to model this situation.

• y = 3x+7

• y = 7x+3

• y = -3x+9

• y = 4x+9

Dominoes charges $6 per pizza. The delivery fee is $4. Write an equation to model this situation.

• y = -4x+6

• y = 6x+4

• y = 1/6x-4

• y = 64x