2-4:%20Writing%20Linear%20Equations%20%20%20%20%20Using%20Slope%20Intercept%20Form

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2-4 Writing Linear Equations Using
Slope Intercept Form
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Slope-Intercept Form

• y mx b or f(x) mx b
• m is the slope
• b is the y-intercept

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Find the Equation of the Line

• What is the
• y-intercept?
• b -2
• What is m?
• m
• y x -2

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Find the Equation of the Line

• b ?
• b 1
• m ?
• m -
• y - x 1

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Find the Equation of the Line

• b ?
• b 4
• m ?
• m 0
• y 0x4
• y4

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Find the Slope and y-intercept of each Equation

• 1) y -4x 3
• m -4
• b 3
• 2) y 5 - x
• m -
• b 5

• 3) 8x y
• m -8
• b
• 4) 4x - 2y 10
• m 2
• b -5

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Find the Equation Given the Slope and y-intercept

• 1) m -3, b 1
• y -3x 1
• 2) m - , b -4
• y - x - 4

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Find the Equation Given the Slope and a Point

• Given m -1, (2, 1)
• First, calculate b by substituting the slope and
  the coordinates into y mx b.
• y -1x b
• 1 -1(2) b
• 1 -2 b
• 3 b
• y -1x 3

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Find the Equation GivenTwo Points

• Given (-1, 3) and (2, 1)
• First, calculate the slope
• Second, find b. Use either point...
• m , (2, 1)
• 1 (2) b
• 1 b
• b