Angle Bisectors

Front

What is an angle bisector?

Back

An angle bisector is a line or ray that divides an angle into two congruent angles.

Front

If an angle measures 58 degrees, what is the measure of each angle formed by its bisector?

Back

Each angle would measure 29 degrees.

Front

What does the term 'congruent' mean in geometry?

Back

Congruent means that two figures or angles have the same size and shape.

Front

How do you find the measure of an angle when given its bisector and one of the resulting angles?

Back

You can double the measure of the known angle to find the measure of the original angle.

Front

If angle DEF is bisected by line EJ and m∠DEJ = 5x + 7 and m∠JEF = 8x - 8, how do you solve for x?

Back

Set the two angles equal to each other: 5x + 7 = 8x - 8, then solve for x.

Front

What is the relationship between the angles formed by an angle bisector?

Back

The angles formed by an angle bisector are always equal.

Front

If m∠JKM = 22 degrees and line KM bisects angle LKJ, what is m∠LKJ?

Back

m∠LKJ = 44 degrees.

Front

What is the measure of angle CBD if angle ABD measures 74 degrees and line AB bisects angle A?

Back

m∠CBD = 37 degrees.

Front

What is the formula to find the measure of an angle when given its bisector?

Back

If m∠A is the original angle, then each angle formed by the bisector is m∠A/2.

Front

What does it mean for two angles to be supplementary?

Back

Two angles are supplementary if the sum of their measures is 180 degrees.