Page 184 - IM_FL_Geometry_Print Sample

Student Response
Because segment appears to be the diameter of our circle, angle must be a right angle.
Activity Synthesis
Ask students to brie y share their thinking. If not mentioned by students, discuss the connection between the inscribed angle and the fraction of the circumference taken up by the arc the angle traces out. Explain to students that whenever a quadrilateral has a circumscribed circle, it is called a cyclic quadrilateral.
11.2 Opposite Angles
10 minutes
The purpose of this activity is to encourage students to conjecture about opposite angles in cyclic quadrilaterals. This leads to proving that opposite angles are supplementary in the next activity.
Launch
Arrange students in groups of 2. Ask students to mark di erent points than their partners so they can compare their cyclic quadrilaterals and decide what seems to always be true.
Student Task Statement
1. Mark 4 points on the circle and label them in order , , , and going counterclockwise around the circle. Use a straightedge to make quadrilateral .
Unit 7
Lesson 11: Circles Outside of Quadrilaterals
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