The construction of copying ∠qpr is started below. the next step is to set the width of the compass to the length of (ab ) .how does this step ensure that the new angle will be congruent to the original angle?

explanation:

previous steps have made pa≅ pb ≅ st ≅ su. setting the compass width to ab allows you to make tu the same length. then δstu ≅ δpab by the sss congruence postulate, and ∠p ≅ ∠s by the reason cpctc.

the answer is 0.3175 hope that you ^w^

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