4.2 Graph Quadratic Functions in Vertex or Intercept Form

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4.2 Graph Quadratic Functions in Vertex or
Intercept Form

• To graph quadratic functions in vertex or
  intercept form
• To write equations in standard form

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Vertex Form
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Characteristics The vertex is (h, k) The axis of
symmetry is x h a controls the width of the
graph and if opens up or down
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(No Transcript)
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Graph y -2(x-3)24
Vertex (3, 4) Fill out a chart. Remember, you
pick the x value and solve for y.
2 1 0
2 -4 -14
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Intercept Form
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Graph y 2(x 3)(x 1)
Steps 1.Plot x intercepts 2. Find axis of
symmetry 3. Find the coordinates of vertex 4.
Plot some pts 5. Connect the dots

• What makes y 0?...-3 1
• -31 -2 then divide in ½ -1
• Plug -1 into equation for x and solve for y.
• Find more pts Pick x and solve for y.

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To Standard Form
Goal Make the equations look like ax2 bx
c Example Write f(x) 4(x-2)2 1 in standard
form
4(x - 2)(x - 2) 1 4(x2 4x 4) 1 4x2
16x 16 1 4x2 16x 17
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Homework

• Pg 249 1 37 Every other odd, 53