Answer:
B=23.19
Step-by-step explanation:
First, find the last side of the triangle using the Pythagorean theorem.
[tex]a^{2} +b^{2} =c^{2} \\21^{2} +9^{2} =c^{2} \\441+81=c^{2} \\\sqrt[3]{58}=c[/tex]
Then, find the missing angle, lets name it B.
The angle B can be found using the inverse sine function.
B=arcsin(opp/hyp)
[tex]B=arcsin(\frac{9}{\sqrt[3]{58} } )\\B=23.19[/tex]
