Unit 6
Glossary
Geometry
A directrix is the line that, together with a point called the focus, defines a parabola.
This diagram shows a parabola is the set of points equidistant from the focus and directrix.
A focus is the point that, together with a line called the directrix, defines a parabola.
This diagram shows a parabola is the set of points equidistant from the focus and directrix.
A median is a line drawn from a vertex of a triangle to the midpoint of the opposite side.
Each dashed line segment in this image is a median.
Two numbers are opposites if they are the same distance from 0 on the number line, but on opposite sides. One is negative, and the other is positive.
From an earlier course.
A parabola is the set of points that are equidistant from a given point, called the focus, and a given line, called the directrix.
Point-slope form is one way to write the equation of a line using its slope and the coordinates of one point on the line.
For a line with slope \(m\) through the point \((h,k)\), point-slope form is usually written as \(y-k=m(x-h)\). It can also be written as \(y = k+m(x-h)\).