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Using Time to Explore Angles. A. endpoints. Look in your book on page 440. Geometry Terms to Know. Line - a straight path between two points that goes on forever in both directions. Point - an exact place in space.
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A endpoints Look in your book on page 440. Geometry Terms to Know Line - a straight path between two points that goes on forever in both directions. Point - an exact place in space. Line Segment - part of a line; has a distinct starting point and ending point.
Look in your book on page 440. Geometry Terms to Know Ray - part of a line; has a definite starting point, but no ending point; goes on forever in one direction. Endpoint
Look in your book on page 440. Geometry Terms to Know Angle - formed by two lines, rays, or line segments that have the same endpoint.
Look in your book on page 440. Geometry Terms to Know Angle - formed by two lines, rays, or line segments that have the same endpoint. This end point is called the vertex.
Geometry Terms to Know We measure angles by measuring the distance between the two sides of the angle.
Geometry Terms to Know We measure this distance in a unit called degrees. The symbol for degrees is a small superscript circle. Degrees = 45°
Types of Angles Let’s use our clocks to discover the names of these angles. There are essentially three different types of angles.
Right Angles Set your clock to 3:00. The hands of the clock form a right angle.
Right Angles Set your clock to 9:00. The hands of the clock form a right angle.
Right Angles Right angles measure exactly 90 degrees.
Acute Angles Set your clock to 2:00. Set your clock to 1:00. The hands of the clocks form acute angles.
Acute Angles Set your clock to 11:00. Set your clock to 10:00. The hands of the clocks form acute angles.
Acute Angles Acute angles measure less than 90 degrees.
Straight Angles Set your clock to 6:00. The hands of the clock form a straight angle.
Straight Angles Straight angles measure exactly 180 degrees.
Obtuse Angles Set your clock to 5:00. Set your clock to 4:00. The hands of the clocks form obtuse angles.
Obtuse Angles Set your clock to 8:00. Set your clock to 7:00. The hands of the clocks form obtuse angles.
Obtuse Angles Obtuse angles measure more than 90 degrees butless than 180 degrees.