| A | B |
|---|
| radius | any line segment that connects the circle's center point to the outside |
| diameter | a line that passes through the center point and touches two sides of the circle |
| chord | a line segment that touches two points of the circle, but not the center |
| congruent figures | figures with the same size and shape |
| symmetry | the figure can be folded in half and fit perfectly |
| similar | figures with the same shape but not always the same size |
| perimeter | the distance around a figure |
| area | the number of square units needed to cover a region |
