Is usually represented by straight line with two arrows to indicate the line extends without end in two directions.
Plane-
Is usually represented by a shape that looks like a tabletop or wall. Although a drawing of a plane has edges it extends without end.
Segement-
A part of a line that consists of of two points called endpoints, all other points are between the endpoints.
Ray-
Part of a line that consists of a point, called an initial point, and all points on the line extend in one direction.
Right angle-
An angle with a measure equal to 90o.
Obtuse angle-
An angle with a measure between 90o and 180o.
Straight angle-
An angle with a measur equal to 180o.
Midpoint-
The point that divides, or bisects, a segement into two congruent segements.
Angle bisector-
A ray that divides an angle into two adjacent angles that are congruent.
Verticle angles-
Two angles whose side form two pairs of opposite rays.
Complementary angles-
Two angles whose measure has the sum of 90o.
Supplementary angles-
Two angles whose measure has the sum of 180o.
Legs-
Are what form the right angle of a triangle.
Hypotenuse-
The side opposite the right angle.
Right triangle-
A triangle with one right angle.
Obtuse triangle-
A triangle with an obtuse angle.
Equilateral triangle-
A triangle with three congruent sides.
Isosceles triangle-
A triangle with at least two congruent sides.
Scalene triangles-
A triangle with no congruent sides.
Polygon-
A plane figure that is formed by three or more sides, where no two sides with a common endpoint are collinear and each side intersects exactly two other lines, one at each endpoint.
Convex polygon-
A side of the polygon that doesn't contain a point in the interior of the polygon.
Concave polygon-
A side of the polygon that contains a point in the interior.
Regular polygon-
A polygon that is equilateral and equilangular.
Parallelogram-
A quadrilateral with both pairs of opposite sides parallel.
Rectangle-
A parallelogram with four right angles.
Rhombus-
A parallelogram with four congruent sides.
Square-
A paralleogram with four right angles and four congruents sides.
Trapeziod-
A quadrilateral with exactly one pair of parallel sides known as bases.
Reflection-
A type of transformation that uses a line that acts like a mirror, called the line of reflection, with an image reflected on the other side.
Rotation-
A type of transformation in which a figure is turned about a fixed point, called the center of rotation.
Translation-
A type of transformation that maps every two points in a plane so they will be collinear.
Similar polygons-
Two polygons such that their corresponding angles are congruent and the lengths of the corresponding sides are proportional.