pc notes c1 s1.notebook
September 08, 2014
Chapter 1 Functions and their Graphs
Sec. 1 Lines in a Plane
­ lines change at a constant rate called slope, usually denoted with an and m. Given two points
change in y
change in x
If the slope of a line is...
positive, m>0
line rises from left to right
negative, m<0
line falls from left to right
zero, m = 0
line is horizontal
undefined
line is vertical
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pc notes c1 s1.notebook
September 08, 2014
Forms of Linear Equations
Point-Slope Form - can be used when you know the slope, m, and a
point on the line
Slope­Intercept Form ­ equation tells you the slope and where the line crosses the y­axis (y­intercept)
y­intercept
slope
General Form ­ can be easy to graph the line in this form by finding the x and y intercepts.
A and B can't both =0, Horizontal ­ Vertical ­ 2
pc notes c1 s1.notebook
September 08, 2014
Parallel & Perpendicular Lines
- parallel lines have equal slopes
equal slope
- perpendicular lines have slopes that are opposite reciprocals of each
other
opposite reciprocals
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pc notes c1 s1.notebook
Example
Write the equation of the line that contains the points Is this line rising or falling from left to right?
September 08, 2014
.
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pc notes c1 s1.notebook
September 08, 2014
Example
Are these lines parallel, perpendicular or neither?
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pc notes c1 s1.notebook
September 08, 2014
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Attachments
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