In RT △ ABC, a = 30.01, ∠ B = 80 ° 24 'and ∠ C = 90 °, right triangle can be solved according to the following conditions
cos∠B=a/c
30.01/ cos(80°24’)= c
c=179.94978...
tan∠B=b/a
30.01* tan(80°24’)= b
b=171.94955...
∠A=90°-80°24’
∠A=9°36’
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