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Slope
The slope of a line is determined by any two points on a line and describes the steepness of the line. It is often referred to as rise and can be calculated using the formula: run
Given two points on the line known as (x1,y1) and (x2,y2):
slope = y2y1x2x1
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Example 1 Find the slope of the line that passes through(1,2) and (3,4).
Use the slope equation: slope = y2y1x2x1
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Example 2 Find the slope of the line that passes through(1,2) and (4,1).
Use the slope equation: slope = y2y1x2x1
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Example 3 Find the slope of the line that passes through(1,2) and (1,2).
Use the slope equation: slope = y2y1x2x1
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Example 4 Find the slope of the line that passes through(1,2) and (1,3).
Use the slope equation: slope = y2y1x2x1
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Example 5 Find the slope of the line that passes through(3,2) and (5,5).
Use the slope equation: slope = y2y1x2x1
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Find the slope between each pair of points.
1. (0,2)(4,0)2. (1,5)(3,0)3. (0,5)(5,0)4. (1,2)(1,4)5. (3,8)(1,4)
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Example 6 Find the slope of the line that passes through(3,4) and (2,8).
Use the slope equation: slope = y2y1x2x1
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Example 7 Find the slope of the line that passes through(2,4) and (2,3).
Use the slope equation: slope = y2y1x2x1
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Example 8 Find the slope of the line that passes through(3,4) and (4,4).
Use the slope equation: slope = y2y1x2x1
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Example 9 Find the slope of the line.
Use the slope equation: slope = y2y1x2x1
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Assignment: page 170 1,46,918,25,31,32,34
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More Slope
Activity:
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Parallel lines have the same slope.
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1. Graph the points A(1,1) and B (4,4) .2. Use a straight edge to draw line AB .3. Graph the points C(1,1) and D(0,0).4. Use a straight edge to draw line CD.5. Label the intersection point E.6. Use a protractor to measure <AEC.7. What is the relationship between line AB and line CD?8. Find the slope of line AB .9. Find the slope of line CD.10. Multiply them together.
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Perpendicular lines have slopes whose product is 1.
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Assignment: page 172 1024
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