Download MPM 1DI - U5 - D1 - Slope Y Intercept Form.notebook

MPM 1DI ­ U5 ­ D1 ­ Slope Y Intercept Form.notebook
MPM 1DI ­ Unit 5 Linear Relations
January 04, 2016
Day 1 ­ Equation of a Line Slope ­ Y intercept Form
Learning Goal: In this lesson I am learning...
- how to connect slope an y-intercept to its equation in slope yintercept form.
- how to interpret the meaning of slope an y-intercept in a realistic
situation.
Success criteria: By the end of to day I will be able to...
- recognize equations in the form y= mx +b
- graph a line given slope and point
- find the slope and y intercept from y = mx + b
- Graph a line from its equation in y= mx + b form
- State the significance of the slope and y-intercept from a graph
representing a realistic situation
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MPM 1DI ­ U5 ­ D1 ­ Slope Y Intercept Form.notebook
January 04, 2016
MPM 1DI ­ U5 ­ D1 ­ Equation of a Line Slope ­ Y intercept Form
Remember: the equation of line can be written
in slope y­intercept form : where m is the slope
y = mx + b , and b is the y­intercept.
Example 1: Determine the slope and y­intercept of each line. Then determine the equation of each linear relation.
L1
L4
slope
(m)
L1
: L2
:
L3
:
y-
equation
intercep
t(b)
y=mx + b
L3
L2
L4
:
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MPM 1DI ­ U5 ­ D1 ­ Slope Y Intercept Form.notebook
January 04, 2016
Example 2: Given the slope and y­intercept, write an equation of the linear relation and then graph the line.
To graph a line given
slope and y­intercept:
Step 1: Plot the y­intercept (0,b)
Step 2: Use the slope value to determine rise and run from the y­intercept value. b. m = ­2, b = 1
d. m = 5, b = 2
Special Cases: A. Horizontal Lines
• The slope of a horizontal line is zero.
• Putting that slope into the equation , we get , y = 0x + b
∴ y = b is the equation of a horizontal line.
B. Vertical Lines
• The slope of a vertical line does not exist. • We call this undefined.
∴we cannot use slope y­intercept form for vertical lines.
• Vertical lines are written in the form of , x = a,
where a is the x­intercept.
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MPM 1DI ­ U5 ­ D1 ­ Slope Y Intercept Form.notebook
January 04, 2016
Example 3: Interpreting graphs
The distance(m) time(sec) graph of a person walking in front of a motion sensor is shown below.
a. How far from the sensor did the person start walking? b. How fast did the person walk?
c. Did the person walk away or towards the sensor?
d. What is happening after 5 seconds? Pg 304­306 # 1, 2, 3, 4, 6(ace), 7(ab), 8, 9, 12
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MPM 1DI ­ U5 ­ D1 ­ Slope Y Intercept Form.notebook
January 04, 2016
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