Recall: Parabolas

Recall:

Parabolas can open up or down.
The zeroes of a parabola is where the graph crosses the x- axis.
The y- intercept of a parabola is where the graph crosses the y- axis.
Zeros are also recognised as the "roots" or "x-intecepts"
The axis of symmetry of divides the parabola in two equal halves.
The axis of symmetry is also the x- coordinate of the vertex.
The obtimal value us the y- coordinate of the vertex.
The vertex of a parabola is a point where the axis of symmetry and the parabola meet. It is the point where the parabola is either maximum or minimum.
The vertex consists of two numbers (x,y) the x value is the axis of symmetry and the y value is the optimal value.

There are three forms of the same equation which represents the graph.

1) Factor Form: -0.1 (x-19) (x+3)

2) Vertex Form: -0.1 (x-8) 2+12

3) Standard Form: -0.1x 2 + 1.6x+11.6