1. EXAMPLE 3
Identify congruent arcs
Tell whether the red arcs are congruent. Explain why or why not. a. b.
SOLUTION a.
CD EF because they are in the same circle and mCD = mEF b.
RS and TU have the same measure, but are not congruent because they are arcs of circles that are not congruent.

2. EXAMPLE 3
Identify congruent arcs
Tell whether the red arcs are congruent. Explain why or why not. c.
SOLUTION c.
VX YZ because they are in congruent circles and mVX = mYZ .

3. GUIDED PRACTICE
for Example 3
Tell whether the red arcs are congruent. Explain why or why not. 7.
SOLUTION
AB CD because they are in congruent circles and mAB = mCD .

4. GUIDED PRACTICE
for Example 3
Tell whether the red arcs are congruent. Explain why or why not. 8.
SOLUTION
MN and PQ have the same measure, but are not congruent because they are arcs of circles that are not congruent.