<u>Part 1) </u>To find the measure of ∠A in ∆ABC, use
we know that
In the triangle ABC
Applying the law of sines

in this problem we have

therefore
<u>the answer Part 1) is</u>
Law of Sines
<u>Part 2) </u>To find the length of side HI in ∆HIG, use
we know that
In the triangle HIG
Applying the law of cosines

In this problem we have
g=HI
G=angle Beta
substitute


therefore
<u>the answer Part 2) is</u>
Law of Cosines
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<span>= Final Price 21 - 4.20 = $16.80
</span>
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