Grade 4 - Progress in Mathematics

Rays and Angles

10-2

J K

Q

P

R

Read the

endpoint first.

When you name an

angle with three letters,

the vertex is always the

middle letter.

Draw and label each figure.

1. 
   DEF 2. ED 3.
   FED 4.
   H 5. ray EF



Name each figure.

Name each angle three ways.

B

A

D E

C

F H

G

K

J I

M

L N P

Q

O

sides

vertex

A ray is the part of a line that starts at an endpoint.

A ray goes on forever in one direction.

Read: ray KJ

Write: KJ

An angle is formed by two rays

with the same endpoint.

The rays form the sides

of the angle.

The common endpoint is the

vertex of the angle.

Read: angle Q, angle PQR, or angle RQP

Write: 
Qor 
PQRor 
RQP



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