# Lesson 11.4: Circles and Arcs

## This lesson contains only examples and exercises related to circles and arcs.

An arc is a portion of a curve or circle. There are two basic braille symbols for arcs:

In print, the symbol for an arc appears over or on top of the letters that define the specified arc. Thus, you must follow the rules for a symbol that appears above the letters.

### Example 1

$\hat{\mathrm{AB}}\phantom{\rule{.3em}{0ex}}\text{is a minor arc.}$

⠸⠩⠀⠐⠠⠁⠠⠃⠣⠫⠁⠻⠀⠸⠱⠀⠊⠎⠀⠁⠀⠍⠊⠝⠕⠗⠀⠁⠗⠉⠲

### Example 2

$\hat{\mathrm{DEF}}\phantom{\rule{.3em}{0ex}}\text{is a major arc.}$

⠸⠩⠀⠐⠠⠙⠠⠑⠠⠋⠣⠫⠁⠻⠀⠸⠱⠀⠊⠎⠀⠁⠀⠍⠁⠚⠕⠗⠀⠁⠗⠉⠲

### Example 3

$m\hat{\mathrm{AB}}={20}^{\circ}$

⠍⠐⠠⠁⠠⠃⠣⠫⠁⠻⠀⠊⠎⠀⠼⠆⠴⠘⠨⠡

### Example 4

$m\hat{\mathrm{AB}}+m\hat{\mathrm{CD}}$

⠍⠐⠠⠁⠠⠃⠣⠫⠁⠻⠬⠍⠐⠠⠉⠠⠙⠣⠫⠁⠻

### Example 5

$\u25efM$

⠫⠉⠀⠠⠍

### Example 6

$\u25efM\cong \u25efP$

⠫⠉⠀⠠⠍⠀⠈⠱⠨⠅⠀⠫⠉⠀⠠⠏

### Example 7

$\hat{\mathrm{AB}}\cong \hat{\mathrm{CD}}$

⠐⠠⠁⠠⠃⠣⠫⠁⠻⠀⠈⠱⠨⠅⠀⠐⠠⠉⠠⠙⠣⠫⠁⠻

### Example 8

$\frac{m\hat{\mathrm{AB}}}{360}$

⠹⠍⠐⠠⠁⠠⠃⠣⠫⠁⠻⠌⠒⠖⠴⠼