Vertex form of a quadratic equation

All we need:

1. the Vertex formula (V)
   Vertex: V(h, k)
   and
2. a quadratic equation in the Vertex form
   Quadratic equation: ax² + bx + c = 0
   The Vertex form: y = a(x - h)² + k

Properties:

• a > 0, parabola opens upwards => Minimum
• a < 0, parabola opens downwards => Maximum

Example:

1. y = 2(x - 1)² + 3
• Vertex: (1, 3)
• 2 > 0, parabola opens upwards (see graph)



2. y = - 3(x + 3)² + 4
• Vertex: (-3, 4)
• - 3 < 0, parabola opens downwards (see graph)

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