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Quadratic Function : Parabola

Quadratic Function:
Parabola : y - k = a ( x - h )2, in which a = 1/(2p)
Vertex: V(h, k)
Axis of symmetry: x = h
Focus: F(h, k + p/2 )
directrix: y = k - p/2
Graphic: Open Upward if p > 0, Open Downward if p < 0
parabola equation y + 5 = 0.125 ( x + 3)^2
y + 5 = 0.125 ( x + 3)2
Vertex (-3, -5)
Axis of symmetry x = -3
Parabola equation y - 5 = - 0.125 ( x - 3 )^2
y - 5 = - 0.125 ( x - 3 )2
Vertex ( 3, 5)
Axis of symmetry x = 3
Graphic: Open Downward
Parabola equation y - 3 = -0.125 x^2
y - 3 = -0.125 x2
Vertex (0, 3)
Axis of symmetry x = 0
Graphic: Open Downward
Parabola equation y = 0.125 ( x + 5 )^2
y = 0.125 ( x + 5 )2
Vertex ( -5, 0 )
Axis of symmetry x = -5
Graphic: Open Upward
Parabola equation:
x - h = a ( y - k )2, in which a = 1/( 2p)
Vertex: V(h, k)
Axis of symmetry: y = k
Focus: F( h + p/2, k)
Directrix: x = h - p/2
Graphic: Open Upward if p > 0 and Open Downward if p < 0