Precalculus Examples

Use the vertex form, , to determine the values of , , and .
Since the value of is positive, the parabola opens up.
Opens Up
Find the vertex .
Find , the distance from the vertex to the focus.
Tap for more steps...
Find the distance from the vertex to a focus of the parabola by using the following formula.
Substitute the value of into the formula.
Simplify.
Tap for more steps...
Simplify the denominator.
Tap for more steps...
Multiply by .
Write as a fraction with denominator .
Multiply and .
Multiply the numerator by the reciprocal of the denominator.
Multiply by .
Multiply by .
Find the focus.
Tap for more steps...
The focus of a parabola can be found by adding to the y-coordinate if the parabola opens up or down.
Substitute the known values of , , and into the formula and simplify.
Find the axis of symmetry by finding the line that passes through the vertex and the focus.
Find the directrix.
Tap for more steps...
The directrix of a parabola is the horizontal line found by subtracting from the y-coordinate of the vertex if the parabola opens up or down.
Substitute the known values of and into the formula and simplify.
Use the properties of the parabola to analyze and graph the parabola.
Direction: Opens Up
Vertex:
Focus:
Axis of Symmetry:
Directrix:
Enter YOUR Problem
Mathway requires javascript and a modern browser.