{{ item.displayTitle }}

No history yet!

Student

Teacher

{{ item.displayTitle }}

{{ item.subject.displayTitle }}

{{ searchError }}

{{ courseTrack.displayTitle }} {{ statistics.percent }}% Sign in to view progress

{{ printedBook.courseTrack.name }} {{ printedBook.name }} Let's first identify the angle we want. The symbol $∠AOC$ refers to the angle found between the rays that start at $O$ and pass through the points $B$ and $D.$

Examining the protractor, we can see that the ray traveling through $A$ passes through $0_{∘}.$ Also, the ray traveling through $C$ passes through $55_{∘}.$ By the Protractor Postulate, the measure of $∠AOC$ is the difference between $55_{∘}$ and $0.$ $m∠AOC:55_{∘}−0_{∘}=55_{∘}$ Now, we can classify the angle using its measure.

Type | Measure |
---|---|

Acute | $0_{∘}<m<90_{∘}$ |

Right | $m=90_{∘}$ |

Obtuse | $90_{∘}<m<180_{∘}$ |

Straight | $m=180_{∘}$ |

Because our angle is $55_{∘},$ we know that it is an acute angle.