# Vertex, Direction

[Vertex, Direction] command generates a parabola, with the vertex point and the symetry axis specified.

## Step 1

For the prompt "Input the vertex of parabola", locate a point of the parabola vertex to generate.

- Pressing `H` key designates if the half part or whole of the parabora be generated.

## Step 2

For the prompt "Input direciton of the parabola", specify a point to define the symetry axis line of the parabola. The straight from the vertex point of Step1 through the point of this step will be the symetry axis.

## Step 3

For the prompt "Input terminate point of the parabola.", locate the end point of the parabola.