Triangle Similarity
The characteristic of figures such that they have the same shape but not necessarily the same size.
Similar
A figure made up of two or more figures.
Composite Figure
The result of dividing the circumference of a circle by its diameter.
Pi
The ratio of two side lengths of a right triangle.
Trigonometric Ratio
The shape created when a rectangular pyramid is sliced so the cross section is perpendicular to the base but does not pass through the vertex.
Trapezoid
If three sides of one triangle are proportional to the three sides of another triangle, then the triangles are similar.
Side-Side-Side (SSS) Similarity Theorem
The type of units used to measure area.
Square units
An angle that has its vertex on a circle and its sides as chords of the circle.
Inscribed Angle
Opposite over Hypotenuse
Sine
The three-dimensional object created when a semicircle is rotated about an axis.
Sphere
If a line is parallel to one side of a triangle and intersects the other two sides in two distinct points, then it separates these sides into segments of proportional lengths.
Triangle Proportionality Theorem
a.k.a. Side-Splitting Theorem
The type of units used to measure volume.
Cubic units
A line in the plane of a circle that intersects the circle in exactly one point.
Tangent
The length of the longer leg of a 30-60-90 special right triangle is the length of the shorter leg times this number.
square root of 3
The three-dimensional object created when a triangle is rotated about an axis.
Cone
These triangles are always similar to each other.
Equilateral Triangles
A solid with two parallel, congruent, circular bases joined by a curved surface.
Cylinder
The measure of a central angle of a circle that intercepts an arc equal in length to the radius of the circle.
Radian
The angle that has a given value as it's tangent ratio.
Inverse Tangent
Population divided by area.
Population Density
This transformation creates similar figures.
Dilation
If two solids have equal heights and the cross sections formed by every plane parallel to the bases of both solids have equal areas, then the two solids have equal volume.
Cavalieri's Principle
In a circle, a region with boundaries of two radii and a part of the circle.
Sector
A line segment that is drawn from the center of a regular polygon to a side and is perpendicular to that side.
Apothem
Mass divided by volume.
Object Density