Answer:
∠B = 60°
Explanation:
Let us first draw the triangle.
Now the law of cosines gives
[tex](15\sqrt{3})^2=30^2+15^2-2(15*30)cosB[/tex]
which simplfies to give
[tex]675=1125-900cosB[/tex][tex]\Rightarrow2\cos B=1[/tex][tex]\cos B=\frac{1}{2}[/tex]
Solving for B gives
[tex]B=\cos^{-1}(\frac{1}{2})[/tex]
Using a calculator we get
[tex]\boxed{B=60^o}[/tex]
which is our answer!
