standard_description: Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint, and understand concepts of angle measurement:
- An angle is measured with reference to a circle with its center at the common endpoint of the rays, by considering the fraction of the circular arc between the points where the two rays intersect the circle. An angle that turns through 1/360 of a circle is called a “one-degree angle,” and can be used to measure angles.
- An angle that turns through n one-degree angles is said to have an angle measure of n degrees.
problem_activity: Problem 1
Bisect the following angle using constructions. Write your steps for construction.
$${\overline{CA}\cong \overline{AB}}$$
[IMG]
Problem 2
You and your partner will be provided with a list of steps (in random order) needed to copy an angle using a compass and straightedge. Your task is to place the steps in the correct order, then follow the steps to copy the angle below.
[IMG]
|                                                Draw circle                     $$B$$                    : center                     $$B$$                    , any radius.                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Label the intersections of circle                     $$B$$                    with the sides of the angle as                     $$A$$                    and                     $$C$$           *           .          * |
|                                                                  Label the vertex of the original angle as                     $$B$$                    .                                                                   |
|                                                                           Draw                     $${\overrightarrow{ED}}$$                    .                                                                           |
|                                                         Draw                     $${\overrightarrow{EG}}$$                    as one side of the angle to be drawn.                                                         |
|                           Draw circle                     $$F$$                    : center                     $$F$$                    , radius                     $$FA$$                    .                           |
|                           Draw circle                     $$E$$                    : center                     $$E$$                    , radius                     $$EA$$                    .                           |
|           Label intersection of circle          *             $$E$$            *          with                     $${\overrightarrow{EG}}$$                    as                     $$F$$                    .           |
|                 Label either intersection of circle                     $$E$$                    and circle                     $$F$$                    as                     $$D$$                    .                  |


aligns: no