PolygonA polygon is a two-dimensional geometric figure with these characteristics:
It is made of straight line segments.
Each segment touches exactly two other segments, one at each of its endpoints.
It is closed - it divides the plane into two distinct r
Chapter 1
Acute TriangleA triangle that has angles less than 90 degrees
AltitudeAn altitude of a triangle is a line segment connecting a vertex to the line containing the opposite
side and perpendicular to that side.
Angle-angle-angle SimilarityThe angle-
Right TriangleA right triangle is a triangle with one right (90) angle.
RotationRotation is a rigid motion, meaning an object changes its position but not its size or shape. In a
rotation, an object is turned about a "center" point, through a particular a
TangentIf angle A is an acute angle in a right triangle, the tangent of A is the length of the side opposite
to angle A divided by the length of the side adjacent to angle A. We often abbreviate this as tan
A = (opposite)/(adjacent).
TangramA tangram is a
HypotenuseThe hypotenuse in a right triangle is the side of the triangle that is opposite to the right angle.
IncenterThe incenter of a triangle is the point where the three angle bisectors meet. This point is the
same distance from each of the three side
Convex PolygonA convex polygon is any polygon that is not concave.
CoordinatesPoints are geometric objects that have only location. To describe their location, we use
coordinates. We begin with a standard reference frame (typically the x- and y-axes). The
MedianA median is a segment connecting any vertex of a triangle to the midpoint of the opposite side.
MidlineA midline is a segment connecting two consecutive midpoints of a triangle.
Midline TheoryThe midline theorem states that a midline of a triangle c