Unit 3 - Lesson 1 (Average Rate of Change)

Unit 3 - Lesson 1 (Average Rate of Change - linear functions)

What is average rate of change?

Average rate of change is the difference between two output values divided by two corresponding input values. When discussing linear functions average rate of change and slope are interchangeable.

Calculating Average Rate of Change

Change in x divided by Change in y

(y₂ - y₁) / (x₂ - x₁)

ex.) If a linear function has the following points on its graph (4, 2), (2, 0). The average rate of change is calculated by assigning 4 as x₁, 2 as y₁, Then in the next ordered pair 2 as x₂ and 0 as y₂.

(0 - 2) / (2 - 4) = -2/-2

The avg. rate of change given the ordered pairs (4,2), (2, 0) is -1.

Multiple Choice

Find the slope of the line that passes through the points (2, 4) and (6, 12)

• 1/2
• -1/2
• 2
• -2

Multiple Choice

Find the slope from the table:

• -2/5
• 5/-2
• 5/2
• 2/5

Multiple Choice

Calculate the average rate of change from 20 to 40 minutes.

• -2 minutes per gallon

• -20 minutes per gallon

• -2 gallons per minute

• -20 gallons per minute

Multiple Choice

What is Mrs. Gordon's rate from 0 to 2 seconds?

• 2.5 feet per second
• .4 feet per second
• 5 feet per second
• .2 feet per second

Multiple Choice

What is the slope?

• Positive
• Negative
  Negative
• Zero
• Undefined

Multiple Choice

What is the Slope?

• Positive
• Negative
• Zero
• No Slope

Multiple Choice

What is the slope?

• Positive
• Negative
• Zero
• Undefined

Multiple Choice

What is the slope?

• Positive
• Negative
• Zero
• No Slope