Answer:
38.4º
Step-by-step explanation:
Use Law of Cosines
c² = a² + b² - 2ab*cosC
12² = 17² + 19² - 2(17)(19)*CosC
Simplify
144 = 289 + 361 - 646 * cosC
144 = 650 - 646 * cosC
Subtract 650 from both sides
-506= -646 * cosC
Divide both sides by -646
0.7832817337 = cosC
Take the arcsin of 0.7832817337
38.4º = C
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Cheaters Solution!!!
Instead of doing the math you could think it through.
Since FD is less than 17
∠E must be less than 45º
So the answer must be A. 38.4º
