1. 4.4 Find Slope and Rate of Change

2. Today’s Learning Targets:
I will find the slope of an equation given two ordered pairs.
I will find the slope of horizontal or vertical lines.
I will relate slope to rate of change.
I will identify positive, negative, zero and undefined slopes from a graph.
I will interpret graphs of real life situations.

3. Rate of change (or slope)
Slope = m

4. Classifying lines by slope…
Positive slope
m > 0
Line rises from left to right
Negative slope
m < 0
Line falls from left to right
No slope
Undefined
Vertical line
Zero slope
m = 0
Horizontal Line

5. Slope = 𝑟𝑖𝑠𝑒 𝑟𝑢𝑛 = 𝑣𝑒𝑟𝑡𝑖𝑐𝑎𝑙 𝑐ℎ𝑎𝑛𝑔𝑒 ℎ𝑜𝑟𝑖𝑧𝑜𝑛𝑡𝑎𝑙 𝑐ℎ𝑎𝑛𝑔𝑒
Counting for Slope Worksheet

6. The table shows the cost to paint a house for a given number of hours
The table shows the cost to paint a house for a given number of hours. Find the rate of change in cost with respect to time.
Time (hours) 4 6 8
Cost ($) 90
135
180

7. A theater performed a play each Saturday for 10 consecutive weeks
A theater performed a play each Saturday for 10 consecutive weeks. The graph shows the attendance for the performances in weeks 1, 4, 6, and 10. Describe the rates of change in attendance with respect to time.

8. Homework:
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