Rewrite in Vertex Form by Completing the Square.notebook
May 28, 2013
Rewriting Quadratic Functions in
Vertex Form
y = ax2 + bx + c
y = a(x - h)2 + k
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Rewrite in Vertex Form by Completing the Square.notebook
May 28, 2013
Converting from Standard form to Vertex Form
y = ax2 + bx +c y = a(x ­ h)2 + k
1. a) Rewrite y = ­3x2 + 24x ­ 28 in y = a(x ­ h)2 + k form.
I. Group the first two terms.
II. Common Factor the coefficient of
the first term.
III. "Complete the Square" on the
terms inside the brackets. I.e. Add
and subtract
in the brackets.
IV. Remove the 4th term from the
brackets. You must multiply by the
Coeffiecient infront of the bracket
first.
V. Factor the perfect square in the
bracket. You should have an equation
in the form y = a(x ­ h)2 + k .
b) State:
Vertex ________
Direction of Opening _____
Axis of Symmetry _____
c)
Find the x ­ intercepts.
d)
Graph using the vertex, x­intercepts, and value of "a".
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Rewrite in Vertex Form by Completing the Square.notebook
May 28, 2013
2. a) Rewrite y = 0.1x2 + 2x + 1 in y = a(x ­ h)2 + k form.
b) State:
Vertex ________
Direction of Opening _____
Axis of Symmetry _____
c)
Find the x ­ intercepts.
d)
Graph using the vertex, x­intercepts, and value of "a".
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Rewrite in Vertex Form by Completing the Square.notebook
May 28, 2013
3. a) Rewrite y = x2 + 6x + 2 in y = a(x ­ h)2 + k form.
b) State:
Vertex ________
Direction of Opening _____
Axis of Symmetry _____
c)
Find the x ­ intercepts.
d)
Graph using the vertex, x­intercepts, and value of "a".
Homework: Page 235 #7, #9(a, c, e, g), #12(a, c) Convert and analyse as in class.
# 2 (a, f), #8(a, d, f)
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Rewrite in Vertex Form by Completing the Square.notebook
May 28, 2013
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Rewrite in Vertex Form by Completing the Square.notebook
May 28, 2013
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