This document provides an overview of geometry. It defines geometry as the study of shapes and figures, and notes how it is used in fields like construction. Key geometry terms are defined, including points, lines, line segments, rays, angles, and classifying angles as right, acute, or obtuse. Standards are listed for third grade geometry focusing on drawing and classifying triangles and identifying geometric properties.

1. Geometry
Ruthelyn B Turner

2. Standards
• MA.3.M3G1 - Students will further develop their understanding of geometric
figures by drawing them. They will also state and explain their properties.
• MA.3.M3G1.a - Draw and classify previously learned fundamental
geometric figures and scalene, isosceles, and equilateral triangles.
• MA.3.M3G1.b - Identify and compare the properties of fundamental
geometric figures.

3. • Geometry is a kind of mathematics that
deals with shapes and figures. Geometry
explains how to build or draw shapes,
measure them, and compare them.
People use geometry in many kinds of
work, from building houses and bridges to
planning space travel.

4. Geometry Terms
• Points, lines, and angles are basic terms of
geometry.
• A point is usually represented by a dot.
• A line is an object that extends without end in
both directions. It has arrow heads on both
ends.
• A line segment is a part of a line with two end
points.
• A ray has one end point and half of a line.

5. • Two rays with the same end point form an
angle.
• If the rays are the two halves of a single line, the
angle is called a straight angle.
• A straight angle can be thought of like a book
opened flat on a desk.
• An angle opened half that far is called a right
angle

6. • Angles are measured in degrees.
• A right angle measures 90 degrees.
They can be found in many different
shapes and objects.
• Acute angles are smaller than a right
angle. (0-89 degrees)
• Obtuse angles are larger than a right
angle but smaller than a straight angle.
(91-179 degrees)

7. Credits
• Geometry: Right Angles. [Video]. Retrieved October 24,
2010, from Encyclopædia Britannica Online School
Edition: http://www.school.eb.com.proxygsu-
slib.galileo.usg.edu/elementary/art-82789
• Geometry. (2010). In Britannica Elementary
Encyclopedia. Retrieved October 25, 2010, from
Encyclopædia Britannica Online School Edition:
http://www.school.eb.com.proxygsu-
slib.galileo.usg.edu/elementary/article?articleId=353174
•