Page 94 - IM_FL_Geometry_Print Sample

• Larger acute angle
• Smaller obtuse angle • Larger obtuse angle
Tell students that two people in the group will make obtuse angles and two people will make acute angles. One person will make a larger obtuse angle, and one person will make a smaller obtuse angle. Similarly, one person will make larger acute angle and one person will make a smaller acute angle. Display 4 angles that meet this criteria for all to see as an example:
Student Task Statement
Your teacher will assign you 1 of these types of angles:
• Smaller acute • Larger acute angle angle
• Smaller obtuse angle
• Larger obtuse angle
1. Construct a diagram as follows:
a. Mark a point and draw ray so that angle matches your angle type. For
example, if your type is the smaller obtuse angle, then angle should be an obtuse angle that is smaller than the angle of the person in your group who has the larger obtuse angle.
b. Construct a circle centered at with radius the arc of this circle enclosed by angle
the radius as .
c. Construct a circle centered at with radius the arc of this circle enclosed by angle
the radius as .
. Use a colored pencil to highlight . Label the length of the arc as and
. Use a colored pencil to highlight . Label the length of the arc as and
2. Explain how you know . In other words, explain why the ratio of arc length to radius is the same, regardless of the size of the circle.
Unit 7
Lesson 2: Measuring Angles 21