Angle – the distance between two rays with a common endpoint
Vertex – the common endpoint of the two rays that form an angle
Degrees – the unit of measure for an angle
Supplementary – two angles whose sum is 180º
Complementary – two angles whose sum is 90º
Linear pair – two adjacent angles that form a straight line
Protractor – the tool used to measure angles.
Obtuse – an angle measuring larger than 90º, but less than 180º
Acute – an angle measuring less than 90º
Reflex – the measurement on the outside of an angle.
Right – an angle measuring exactly 90º
Straight – an angle measuring exactly 180º
Adjacent Angles – angles with a common endpoint and a common ray
Vertical Angles – opposite angles formed by the intersecting of two lines.
Angle Bisector – a line or ray that divides an angle in half
Theorem – A rule that has been proven and can be universally accepted as true.
Congruent – having the same measure
Transversal – a line that intersects two other lines
Alternate Interior – angles on the inside of a set of lines on opposite sides of a transversal
Alternate Exterior – angles on the outside of a set of lines on opposite sides of a transversal
Corresponding Angles – angles that are in the same position in the set of angles created by lines being intersected by a transversal
Consecutive Interior – angles on the inside of a set of lines and on the same side of a transversal
Converse – Switching the hypothesis and conclusion of a conditional statement
Corollary – a continuation or extension of a theorem or postulate.