This document discusses linear functions. It defines a linear function as one that graphs as a straight line. The equation of a line is given as y = mx + b, where m is the slope and b is the y-intercept. Several examples of linear functions are graphed and their slopes and y-intercepts identified. The document also provides examples of evaluating linear functions for given values of x.

1. Ch2.3_LinearFunctions.notebook September 12, 2011
Warm Up
Are these functions?
{(1,2)(2,3)(3,2)(1,­2)}
y = |x+2| ± 3
Chapter 2.3
Linear Functions
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2. Ch2.3_LinearFunctions.notebook September 12, 2011
Linear Function
When graphed, it will be a straight line
y = x + 2
or
f(x) = x + 2
Graph y = 2x + 3
x y
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3. Ch2.3_LinearFunctions.notebook September 12, 2011
Equation of a Line
y = mx + b
m is the slope
b is the y­intercept
Graph y = 3x + 1
Slope =
y­intercept =
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4. Ch2.3_LinearFunctions.notebook September 12, 2011
Graph y ­ 8 = 2x
Slope =
y­intercept =
Graph 3x + y = 1
Slope =
y­intercept =
4

5. Ch2.3_LinearFunctions.notebook September 12, 2011
Graph y = 4
Slope =
y­intercept =
Graph x = ­2
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6. Ch2.3_LinearFunctions.notebook September 12, 2011
Graph y = |x|
x y
Graph y = ­|x­1| + 2
x
y
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7. Ch2.3_LinearFunctions.notebook September 12, 2011
2
f(x) = x ­ 2
f(1) =
f(2) =
f(­4) =
f(x) = 3|x| ­ |2x ­ 1|
f(­1) =
f(5) =
f(­3) =
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8. Ch2.3_LinearFunctions.notebook September 12, 2011
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