f(x) = a(x− h)2 + k, a 6= 0

vertex = (h, k)

axis of symmetry: x = h

a > 0 → concave upa < 0 → concave down

h > 0 → h units to the righth < 0 → |h| units to the left

k > 0 → k units upk < 0 → |k| units down

f(x) = ax2 + bx + c

Vertex =(−b

2a , f(−b

2a

))

To solve for x-intercept:let f(x) = 0 and solve for x

To solve for f(x)-intercept:let x = 0 and solve for f(x)

Quadratic Formula:

x = −b±√

b2 − 4ac2a

Quadratic Function Notes Created by: Matthew Westerhoff, 2006

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