Slope

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Slope

• Objectives
• I CAN find and use the slope of a line.
• I CAN use the slope to determine whether lines
  are parallel or perpendicular.

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Slope
Slope (m)
how steep a line is rate of change (mph)
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Finding Slope Using 2 Points
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Example 1
Whats the slope of the line through the points
(-1, 3) and (2, -1)?
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Four Types of Lines
Positive Slope rise from L-R
Negative Slope falls from L-R
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Four Types of Lines
Zero Slope horizontal
Undefined Slope vertical
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Parallel Lines
same slope
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Perpendicular Lines
opposite reciprocal slopes (product is -1)
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Example 2
Parallel or perpendicular?Line 1 (-2, 2), (0,
-1) Line 2 (-4, -1), (2, 3)
Opposite Reciprocals
Perpendicular Lines
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