# Linear Functions Assessment

1. Use the formula to complete the table: y = 3 + 2(2x − 5).

 Input(x) Output(y) 3 4 6 10
2. Find the missing values and the rules for x.

 Input1 Output1/Input2 Output2 1 5 15 3 7 21 5 9 27 9 16 x
3. At the start of an experiment, a bacteria colony has an area of 22 cm2. It grows at a constant rate of 3 cm2 per day. Fill in the table and come up with a rule for predicting the area of this bacteria colony on day x.

 Day Area (cm2) 0 1 2 3 4 28 55
4. Bob uses the following rule to predict the area of a bacteria colony on day x: area = 21 + 4x. How fast is the colony growing? What was its area at the start of the experiment? Explain how you can tell by looking at the rule.

5. Find the rule to predict the area of the bacteria colony on day x.

 Day Area (cm2) 0 5 32 9 52 13 72 17 92
6. The area of a bacteria colony is 24 cm2 at the start of an experiment. For the first three days, the colony shrank at a rate of 3 cm2 per day. For the next five days, the area of the colony grew at a rate of 4 cm2 per day. For the last two days, the area of the colony did not change. Fill in the table for this experiment.

 Day Area (cm2) 0 1 2 3 4 5 6 7 8 9 10

Use the graph to answer problems 7-10 and the bonus.

1. Which bacteria colony is growing at a constant rate for the entire experiment? How can you tell just by looking at the graph?

2. When is Bacteria Colony B growing faster than Bacteria Colony A? How can you tell just by looking at the graph?

3. What was the average growth per day for Bacteria Colony B between days 4 and 7?

4. Describe the growth of Bacteria Colony B over time. Explain when it is growing faster or slower, when it is shrinking, and when it is staying the same size.

5. Bonus: Write a rule for the growth of Bacteria Colony A over time.