Unit 2: Graphing Equations
Lesson 5: Graphing Using Slope Intercept Form
Notes
Example 1
Slope = ________
Y-intercept = __________
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Example 2
Slope = ________
Y-intercept = __________
Unit 2: Graphing Equations
Example 3
Example 4
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Unit 2: Graphing Equations
Lesson 5: Using Slope Intercept Form to Graph Equations
Directions: Graph each equation using the following directions:
Example:
1. Circle the y-intercept in the equation.
y = 1/2x +2
Then plot this point on your graph.
(0,2)
2. Put a square around the slope in the
equation.
Then use the slope to plot your next point.
y = ½ x +2
Rise = 1 (up 1)
Run 2 (right 2)
3. Draw a line through your two points.
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Unit 2: Graphing Equations
1.
3.
y = 2x +2
y = 1/3x - 4
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2.
y = -3x +1
4.
y = -2/5x - 2
Unit 2: Graphing Equations
5.
7.
y = -3/4x
y = -2
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6.
y = x +5
8.
y = -4x
Unit 2: Graphing Equations
9. Which graph represents the equation: y = -2/3x – 7?
A. Line A
B. Line B
C. Line C
D. Line D
10. Graph the equation: y = 3x -8
on the grid. Label this line A.
Identify three solutions for this
equation.
11. Graph the equation: y = -x +10
on the grid. Label this line B.
Identify three solutions for this
equation.
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Unit 2: Graphing Equations
1. Which line on the graph represents the equation: y = -3/4x – 2? (1 point)
A. Line A
B. Line B
C
D
C. Line C
D. Line D
B
A
Part 2: Identify the slope and y-intercept in each equation. Then graph the equation on the grid.
(3 points each)
1. y = 3x -6
2. y = -1/4x
Slope: _______
Slope: __________
Y-intercept:_________
Y-intercept:___________
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Unit 2: Graphing Equations
Lesson 5: Using Slope Intercept Form - Answer Key
1.
3.
y = 2x + 2
y = 1/3x - 4
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2.
y = -3x +1
4.
y = -2/5x - 2
Unit 2: Graphing Equations
5.
y = -3/4x
**The y-intercept is (0,0). When no
number is written in the y-intercept’s
place, it is assumed to be 0.
7.
y = -2
**There is no variable term in this
equation; therefore the slope is 0.
Anytime the slope is 0, the line is
horizontal. Therefore, we have a
horizontal line through the y-intercept.
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6.
y=
x +5
**The slope is 1. When there is no
coefficient (slope), the slope is assumed
to be 1. (1 times x is still x)
8.
y = -4x
**The y-intercept is (0,0). When no
number is written in the y-intercept’s
place, it is assumed to be 0.
Unit 2: Graphing Equations
9. Which graph represents the equation: y = -2/3x – 7?
A. Line A
B. Line B
C. Line C
D. Line D
Since the equation has a slope of
-2/3, you can eliminate C and D
because both lines have a
positive slope (rising from left to
right.)
The equation y = -2/3x – 7 has a
y-intercept of -7. Therefore, letter
B, must be the correct answer
because the line passes through
the point (0, -7).
Letter B has a slope of -2/3.
10. Graph the equation: y = 3x -8
on the grid. Label this line A.
Identify three solutions for this
equation.
Possible solutions:
(4,4) (3,1) (2,-2) (1,-5) (0,-8)
(Or any point on the line)
11. Graph the equation: y = -x +10
On the grid. Label this line B.
Identify three solutions for this
equation.
Possible solutions:
(0,10) (1,9) (2,8) (3,7) (4,6)
(Or any point on the line)
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y-intercept = -7
Unit 2: Graphing Equations
1. Which line on the graph represents the equation: y = -3/4x – 2? (1 point)
A. Line A
B. Line B
C
D
C. Line C
D. Line D
B
A
Line B has a y-intercept of -2. The
slope is -3/4, so if you count down
three and right 4, you will end up on
the next point on the line. The slope is
negative, so you can immediately
eliminate letter D since its slope is
positive.
Part 2: Identify the slope and y-intercept in each equation. Then graph the equation on the grid.
(3 points each)
1. y = 3x -6
2. y = -1/4x +0
Slope: 3
Slope: -1/4
Y-intercept: -6
Y-intercept: 0 (this is the origin)
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