acute triangle

A triangle where all three internal angles are acute (less than 90 degrees).

altitude (of a triangle)

The definition of the altitude of a triangle is a line that extends from one vertex of a triangle perpendicular to the opposite side.

cpctc

Corresponding Parts of Congruent Triangles are Congruent

Line Segment

A line segment is a part of a line that is bounded by two distinct end points, and contains every point
on the line between its end points.

Complementary angle

The Complementary Angles are angle whose measures sum to 90 degrees.

Midpoint

The midpoint is the middle point of a line segment.

angle bisection

An angle bisection divides the angle into two angles with equal measures.