How do you solve the triangle given ∠B = 99°, ∠C = 47°, b = 23?

1 Answer
Aug 21, 2016

in DeltaABC, m/_A=34^@, a=13.02, c=17.03.

Explanation:

m/_B+m/_C=99^@+47^@=146^@.

:. m/_A=180^@-146^@=34^@.

Now, we know the Sine-Rule (in usual notation) from Trigo. :

In DeltaABC, a/sinA=b/sinB=c/sinC.

:. a/(sin34^@)=23/(sin99^@)=c/(sin47^@).

:. a=(23sin34^@)/(sin99^@)=(23)(0.5592)/0.9877=13.02.

rArr c=(23sin47^@)/(sin99^@)=(23)(0.7314)/0.9877=17.03

Thus, in DeltaABC, m/_A=34^@, a=13.02, c=17.03.

Enjoy Maths.!