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A–F

AA similarity theorem
Unit 4 Lesson 3

Two triangles are similar if they have two corresponding angles that are congruent.

two triangles representing AA similarity theorem
adjacent
Unit 4 Lesson 7
angles and triangles with adjacent angles marked222111BACDABC
adjacent angles
Unit 3 Lesson 6

Two non-overlapping angles with a common vertex and one common side.

and are adjacent angles:

adjacent anglescommonvertexcommon side12
alternate exterior angles
Unit 3 Lesson 6

A pair of angles formed by a transversal intersecting two lines. The angles lie outside of the two lines and are on opposite sides of the transversal.

See angles made by a transversal.

lines crossing creating alternate exterior angles
alternate interior angles
Unit 3 Lesson 6

A pair of angles formed by a transversal intersecting two lines. The angles lie between the two lines and are on opposite sides of the transversal.

See also angles made by a transversal.

lines crossing creating alternate interior angles12transversalbetweenthe lines
altitude
Unit 3 Lesson 4, Unit 4 Lesson 6

Altitude of a triangle:

A perpendicular segment from a vertex to the line containing the base.

Altitude of a solid:

A perpendicular segment from a vertex to the plane containing the base.

altitude of triangles and cones marked ACDBHMGFEFDEJ
angle
Unit 1 Lesson 3

Two rays that share a common endpoint called the vertex of the angle.

lines creating angles
angle bisector
Unit 3 Lesson 4

A ray that has its endpoint at the vertex of the angle and divides the angle into two congruent angles.

a line cutting and angle in half
angle of depression/angle of elevation
Unit 4 Lesson 9

Angle of depression: the angle formed by a horizontal line and the line of sight of a viewer looking down. Sometimes called the angle of decline.

Angle of elevation: the angle formed by a horizontal line and the line of sight of a viewer looking up. Sometimes called the angle of incline.

angle of elevation ad depression horizontalhorizontalangle ofdepressionangle ofelevation
angle of rotation
Unit 1 Lesson 3

The fixed point a figure is rotated about is called the center of rotation. If one connects a point in the pre-image, the center of rotation, and the corresponding point in the image, they can see the angle of rotation. A counterclockwise rotation is a rotation in a positive direction. Clockwise is a negative rotation.

angle of rotationpositive rotationD is the center of rotationnegative rotation
angles made by a transversal
Unit 3 Lesson 6
angles made by transversalcorresponding anglessame-side interior anglesAngles made by atransversal andparallel linesalternate exterior anglesalternate interior angles12135416
asymptote
Unit 7 Lesson 7

A line that a graph approaches, but does not reach. A graph will never touch a vertical asymptote, but it might cross a horizontal or an oblique (also called slant) asymptote.

Horizontal and oblique asymptotes indicate the general behavior of the ends of a graph in both positive and negative directions. If a rational function has a horizontal asymptote, it will not have an oblique asymptote.

Oblique asymptotes only occur when the numerator of has a degree that is one higher than the degree of the denominator.

a diagram showing vertical asymptotes between curvesverticalasymptoteverticalasymptote
a diagram showing the oblique asymptote within a 1/x functionobliqueasymptote
a diagram showing the horizontal asymptote within a 1/x functionhorizontal asymptote
auxiliary line
Unit 2 Lesson 5

An extra line or line segment drawn in a figure to help with a proof.

auxiliary line12345

is an auxiliary line (added to the diagram of to help prove that the sum of the angles .

binomial
Unit 5 Lesson 6

A polynomial with two terms.

a binomial of (ax b)termtermaddition or subtraction
bisect (verb); bisector (noun) (midpoint)
Unit 1 Lesson 5

To divide into two congruent parts.

A bisector can be a point or a line segment.

bisector