TO 7th grade

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• TO 7th grade
• RSP MATH

Mrs.Muljodiredjo
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Objective

• When given two points, students will be able to
  calculate the slope of the line using the slope
  formula
• M Y1 - Y2
• X1 - X2
• 
  

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CARTESIAN COORDINATE SYSTEM
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I

• René Descartes
• Coordinate Plane

Y

• Coordinate plane consists of
• X axis - a horizontal line.
• Y axis a vertical line.
• Coordinate plane is divided
• into 4 quadrants
• Quadrant I (,)
• Quadrant II (-,)
• Quadrant III (-,-)
• Quadrant IV (,-)

I
II
X
III
IV
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How to graph a
Point ?

1. ( X, Y )
2. X represent the number on the X axis and Y
   represent the number on the Y axis.
3. Find the number on the number line on the X axis
   (horizontal line)
4. Then find the number on the Y axis (vertical
   line)
5. The intersection where those two points meet will
   be the point you need to graph ( X,Y )

• Point on the graph

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How to create a line ?
A

• Lets say point A (2,3)
• and point B (-3,-4)

• Plot point A (2,3) and
• point B (-3,-4) on the graph

• Connect point A and point B
• to create a straight line
• on the graph.

B
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What is SLOPE?

• SLOPE is defined as the change in the Y
  coordinate divided by the change in the X
  coordinate, to measure the steepness of the line.
• Slope is abbreviated as M
• M rise
• run

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SLOPE FORMULA

1. Label the first point as (X1,Y1)
2. Label the second point as (X2,Y2)
3. Plug in the value of X and Y into the slope
   formula
4. Solve and find the value of M (slope)

• M Y1 Y2
• X1 X2

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EXAMPLE

• Find the Slope of the following points
• (-3,4) and (2,-1)
• Let (X1,Y1) and (X2,Y2)
• M Y1 Y2
• X1 - X2
• M 4 -1 5
• -3 2 -5

(-3,4)
-5
5
(2,-1)
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V E R TI C A L L I N E
SPECIAL
CASES FOR SLOPE
Has UNDEFINED slope
HORIZONTAL LINE has a slope of ZERO
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LETS PRACTICE

• FIND THE SLOPE OF
• THE FOLLOWING POINTS
• (6,9) and (2,5)
• (3,8) and (6,-10)
• (4,11) and (-5,-3)

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WHAT WE LEARNED TODAY?

• Cartesian Coordinate Plane
• Graphing a point
• Connecting 2 points to create a line
• Finding a slope of the line by using the slope
  formula M Y1 Y2
• X1
  X2

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Mrs.Muljodiredjo
Together we make the best happen !
MILLIKAN MIDDLE SCHOOL
Sherman Oaks, California
2007