1.3: Measuring and Constructing Angles
Definitions:
Angle - A figure formed by two rays, or sides, with a common endpoint called a vertex.
Interior of an Angle- The set of all points between the sides of the angle.
Exterior of an Angle - The set of points outside of the angle.
- Measure of an angle is interior of an angle, measured in degrees.
- One degree is 1/360 of a circle.
- Angles can be measured with protractors.
Acute Angle - An angle thatmeasures greater than 0º and less than 90º.
Right Angle - An angle that measures 90º.
Obtuse Angle- An angle that measures greater than 90º and less than 180º.
Straight Angle - An angle formed by two opposite rays and measures 180º.
Congruent Angles - Angles that have the same measure.
Angle Bisector - A ray that divides an angle into two congruent angles.
Postulates:
Postulate 1-3-2 - If S is the interior of angle PQR then the measure of angles PQS and SQR= the measure of angle PQR.
Definitions:
Angle - A figure formed by two rays, or sides, with a common endpoint called a vertex.
Interior of an Angle- The set of all points between the sides of the angle.
Exterior of an Angle - The set of points outside of the angle.
- Measure of an angle is interior of an angle, measured in degrees.
- One degree is 1/360 of a circle.
- Angles can be measured with protractors.
Acute Angle - An angle thatmeasures greater than 0º and less than 90º.
Right Angle - An angle that measures 90º.
Obtuse Angle- An angle that measures greater than 90º and less than 180º.
Straight Angle - An angle formed by two opposite rays and measures 180º.
Congruent Angles - Angles that have the same measure.
Angle Bisector - A ray that divides an angle into two congruent angles.
Postulates:
Postulate 1-3-2 - If S is the interior of angle PQR then the measure of angles PQS and SQR= the measure of angle PQR.
Examples: