Q:
# What is the directrix of a parabola?

**The directrix of a parabola refers to a straight line that is drawn perpendicular to the axis of symmetry of a parabola.** This line does not touch the parabola at any point. In addition, it is a horizontal line if the axis is vertical.

To draw a parabola, one has to start with the directrix and a point, known as focus that is off to one side. The parabola, which is the curve, is then formed from all points that are equidistant from the focus and the directrix. The axis of symmetry is a perpendicular line to the directrix that splits the parabola in the middle and passes through the focus.

Learn more about Geometry-
Q:
## What is the standard form of a parabola?

A: The standard form of the equation for a parabola is y = ax^2 + bx + c. A parabola is the set of all points in a plane that are equidistant from a given lin... Full Answer >Filed Under: -
Q:
## What is a ray in geometry?

A: In geometry, a ray is a straight line extending infinitely from a fixed point. A ray is expressed using an arrow as its symbol (---). A ray cannot be measu... Full Answer >Filed Under: -
Q:
## What angle is zero degrees?

A: A zero degree angle appears as a straight line that travels from the point of inception to the right or positive side of a number line. If the line travels... Full Answer >Filed Under: -
Q:
## What is a horizontal line?

A: A horizontal line is a straight line that goes from left to right, which can be open or closed in form. On a coordinate plane, a horizontal line runs paral... Full Answer >Filed Under: