Math 025 Section 7.2 Graphing

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Math 025 Section 7.2 Graphing
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Objectives

• to graph an equation in the form y mx b

• to graph an equation in the form Ax By
  C

• to solve application problems

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Graph y -3x 2 2
y -3x 2 2
x
y
-2
5
0
2
2
-1
4
Graph y 3x 5
y 3x 5
x
y
-1
-8
0
-5
1
-2
5
Graph 2x 3y 6
2x 3y 6
-3y -2x 6
y
y 2x 2 3
x
y
x
-3
-4
0
-2
3
0
6
Graph x 4y 8
x 4y 8
4y -x 8
y
y -x 2 4
x
y
x
-4
3
0
2
4
1
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Problem Graph x 5
Find any two points that have 5 as the
x-coordinate.
y
Draw the line.
x 5
x a is always a vertical graph
Problem Graph y -2
x
y -2
Find any two points that have -2 as the
y-coordinate.
Draw the line.
y b is always a horizontal graph
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A local car dealer is advertising a 2-year lease
on a Honda Civic. The upfront cost is 3000 and
the monthly payment is 150. The total cost,
C, after x months is given by C 150x 3000.
Graph this equation for 0 x 24.
x
C
C 150x 3000
C
0
3000
12
4800
(18, 5700)
24
6600
5000
Total Cost
The point (18, 5700) is on the graph.
Write a sentence that describes this point.
x
12
24
The ordered pair (18, 5700) means that the total
cost of the lease for 18 months is 5700
months