Math unit 4 vocabulary Flashcards
Dilation
Scale factor k>0 and center (0,0) maps (x,y) to (kx, ky)
Isometry
A transformation that preserves length, angle measure, and area.
Rigid transformation
Another name for isometry.
Acute triangle
Three acute angles
Equiangular triangle
Three congruent acute angles
Right triangle
One right angle
Obtuse triangle
One obtuse angle
Equilateral triangle
Three congruent sides
Isosceles triangle
At least two congruent sides
Scalene triangle
No congruent sides
Auxiliary line
A line that is added to a figure to aid in a proof.
Interior
The set of all points inside the figure.
Exterior
The set of all points outside the figure.
Interior angle
Formed by two sides of a triangle.
Exterior angle
Formed by one side of a triangle and the extension of an adjacent side.
Remote interior angle
An interior angle that is not adjacent to the exterior angle.
Corresponding angles and corresponding sides
In the same position in polygons with an equal number of side.
Congruent polygons
Two polygons if and only if their corresponding angles and sides are congruent.
Triangle rigidity
Gives you a shortcut for proving two triangles are congruent.
Included angle
An angle formed by two adjacent sides of polygon.
Included side
The common side of two consecutive angles in a polygon.
CPCTC
An abbreviation for the phrase “Corresponding Parts of Congruent Triangles are Congruent”
Coordinate proof
Style of proof that uses coordinate geometry and algebra.
Legs (of an isosceles triangle)
The congruent sides.
Vertex angle
The angle formed by the legs.
Base
The side opposite the vertex angle.
Base angles
The two angles that have the base as a side.
