McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
1. Ratios and Proportions
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Exercise 62 Page 549

∠3,∠5

Practice makes perfect
Let's begin with recalling the Exterior Angle Inequality Theorem. This theorem tells us that the measure of an exterior angle of a triangle is greater than the measure of either of its corresponding remote interior angles.

Now, let's look at the given picture. As we can see, ∠3 and ∠5 are exterior angles of a triangle containing ∠10. Therefore, the measures of angles 3 and 5 are greater than the measure of ∠10.

There are two angles, 3 and 5, that have greater measure than ∠10. Notice that ∠1 is not an exterior angle of a triangle containing ∠10 and we cannot use the recalled theorem.