PROPERTIES OF CIRCLES

c:::J_O~p~e_n_l_n_y~e~s'~iLg~a'~i~o~n~7~.~8~ ____________________________ _~ PARALLEL LINES THROUGH A CIRCLEStep 1:Take one of your patty papers with a circledrawn on it. Use your straightedge to draw apair of parallel lines passing through the circle.Step 2:Compare the sizes of the arcs between the parallel lines. How do the lengths of thearcs compare?Step 3: Repeat steps 1 and 2 with another pair of parallel lines. (If possible, use a ruler with adifferent width to draw your lines.)Compare your results with the results of others near you. Write a conjecture about the lengths of thearcs formed between a pair of parallel lines.~5'c:::J_O~p_e_n_l_n_y_e_s'~ig~a_'_io_n __ 7_._9 _______________________________~ CYCLIC QUADRILATERALSStep 1:Start with a circle on a party paper, and folda cyclic quadrilateral.- ,, ,Step 2: Trace your cyclic quadrilateral onto another patty paper., ,, ,Step 3: Rotate and slide the copy over the original and look for any relationships between pairsof angles.Step 4: Copy a pair of opposite angles so that they share a vertex and a side. Do this with the otherpair of opposite angles. What do you notice about the sum of the measures of the angles ineach case?Step 5: Repeat steps 1-4 with another cyclic quadrilateral.Compare your results with the results of others near you. Write a conjecture about the relationshipbetween a pair of opposite angles in a cyclic quadrilateral.~52PROPERnES OF CIRCUS 11 9