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Running Circles Around Quads Name ___________________________ CirclesAroundQuads.tns Class ___________________________ Problem 1 – Properties of Parallelograms A cyclic quadrilateral is a quadrilateral inscribed in a circle. Page 1.3 shows cyclic quadrilateral QUAD and the measures of angles Q, U, A, and D. 1. Drag point Q to four different positions and collect data in the table below Position ∠Q ∠U ∠A ∠D 1 2 3 4 2. What do you notice about the opposite angles of a cyclic quadrilateral? 3. Redefine (MENU > Actions > Redefine) point Q (on page 1.3) to be a point not on the circle. Drag point Q to two points inside and two points outside the circle and collect data in the table below. Position ∠Q ∠U ∠A ∠D 1 2 3 4 4. What do you notice about the opposite angles of a quadrilateral that is not necessarily cyclic? Answer the following questions with always, sometimes, or never. Use what you know about the opposite angles of special quadrilaterals (parallelogram, rectangle, kite, trapezoid, etc.) and what you know about the opposite angles of cyclic quadrilaterals. 5. A kite is ________________ a cyclic quadrilateral. ©2010 Texas Instruments Incorporated Page 1 Running Circles Around Quads Running Circles Around Quads 6. A trapezoid is ________________ a cyclic quadrilateral. 7. An isosceles trapezoid is ________________ a cyclic quadrilateral. 8. A parallelogram is ________________ a cyclic quadrilateral. 9. A rectangle is ________________ a cyclic quadrilateral. 10. A square is ________________ a cyclic quadrilateral. 11. A rhombus is ________________ a cyclic quadrilateral. Problem 2 – Extension For this problem, we will look at the angle properties created by the diagonals of cyclic quadrilaterals. 12. Page 2.2 shows the measures of angles Q, U, A, D, DQA, and DUA. Move point D between Q and A to four different points and collect data in the table below. Position ∠Q ∠U ∠A ∠D ∠DQA ∠DUA 1 2 3 4 13. What do you notice about the measure of angles DQA and DUA? ©2010 Texas Instruments Incorporated Page 2 Running Circles Around Quads .

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