SOLUTION: Solve the triangle. 30) b = 18, c = 32, A = 81°

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Question 1131918: Solve the triangle.
30) b = 18, c = 32, A = 81°
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the triangle.
30) b = 18, c = 32, A = 81°
---------
Use the Cosine Law to find side a.
Then the Law of Sines.

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
given:
b=18
c=32+
A=81

use law of cosine, given b,A,c solve for

a+=+sqrt%28+18%5E2+%2B+32%5E2+-+2%2A18%2A32+%2A+cos%28+81%29%29
a+=+sqrt%28+324%2B+1024+-+1152%2A0.15643446504%29
a+=+sqrt%281167.78749627392%29
a+=+34.173+


use law of sines to find angle B
+18%2Fsin%28B%29=+34.173%2Fsin%2881%29
+18%2Fsin%28B%29=+34.173%2F0.987688340595
+18%2Fsin%28B%29=+34.59897
+18=+34.59897sin%28B%29
+18%2F34.59897=sin%28B%29
+sin%28B%29=0.5202467009856
+B=sin%5E-1%280.5202467009856%29
+B=31.34880116598°
+B=31.35°


Since the sum of the three angles is 180°,
C+=+180+-+%28+81+%2B+31.35+%29°
C=+67.65°