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Searching for ## Angles

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Explore the full path to learning Angles

Geometry

You get to learn all about angles–including how to measure them and what it means for them to be congruent.

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After completing this tutorial, you will be able to complete the following:

- Define congruent angles.

In the Animation, and are rearranged to overlap completely. What does this mean about the measure of the two angles? How do we write this relationship with symbols

~ Since the sides and corners of the two angles completely overlap, the angles have equal measures. We write this as .

What does it mean for two angles to be congruent? How do we write this with symbols?

~ Angles with equal measures are congruent. We use the symbol to say that two angles are congruent. For example, since in the Animation, we know that and are congruent angles, and we write .

Consider the following angles:

Which of these are congruent angles?

~ We can see that and have the same measure (they can be made to overlap), so that and are congruent angles. None of the other angles have the same measure as or (they cannot be made to overlap), and no pair of those angles have the same measure. Therefore, and are the only congruent angles among the five given.

Approximate Time | 2 Minutes |

Pre-requisite Concepts | Students should be able to define angle measure, angles, and angles with equal measure. |

Course | Geometry |

Type of Tutorial | Animation |

Key Vocabulary | angle measure, angles, angles with equal measure |