Download 2-2 Linear Functions p

9/3/09
2-2 Linear Functions
2-2 Linear Functions p. 60
Graphing on the calculator
A complete graph is when the xand y- intercepts are seen on
the viewing window.
Standard viewing window is
zoom 6.
[-10, 10] x [-10, 10]
p. 59
1 – 12 practice
2. y = -5x – 6
4. y =-7x + 22
5. y = 5x – 35
6. y = -8x + 32
7. y = 0.1x - 1
8. y = -12x
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9. y = 0.5x + 12
10. y = 0.01x
11. y = x – 55
12. y = 100x - 126
An equation whose graph is a
line is called a linear equation.
Linear equations may contain
one or two variables, but the
exponent is always one.
Linear equations:
y = 6x + 7
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2-2 Linear Functions
y = 5x – 35
5x + y = -6
y=4
x = -8
Forms of a linear equation:
Standard
Slope-intercept
Point-slope
Standard Form of a Linear
Equation
Ax + By = C
Where A, B, and C are integers
and A and B are not both zero
and A is not negative.
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Example 1
Write the equation y = x + 3 in
standard form.
y=x+3
Example 2
Write in standard form:
x = 2/7 + y
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Example 3
Write in standard form:
y = 7/12 x + 1
Definition of linear function
A function is linear if it can be
defined by f(x) = mx + b, where
m and b are real numbers.
m or b may be zero.
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m is the slope
b is the y-intercept –where the
graph crosses the y-axis
If m = 0, then f(x) = mx + b
becomes
f(x) = 0x + b
=b
f(x) = b is a constant function.
The graph is a horizontal line.
f(x) = 0 is called the zero
function.
How to graph an equation:
2x + 3y = 6
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7
I. Make a table. Choose at
least 3 values for x and solve for
y.
II. Determine the x- and yintercepts.
Let x = 0 and solve for y
Let y = 0 and solve for x
III. Put in slope-intercept form
and graph using the slope and yintercept.
y = mx + b
m is the slope
b is the y-intercept
p. 62
1.
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2-2 Linear Functions
Assignment:
p. 62 problems 12 – 36 even
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