Answer:
[tex]46.2^o[/tex]
Step-by-step explanation:
The correct question is
If b = 9 and c = 13, what is the measure of ∠A? (round to the nearest tenth of a degree)
The picture in the attached figure
we know that
In the right triangle ABC
[tex]cos(A)=\frac{b}{c}[/tex] ---> by CAH (adjacent side divided by the hypotenuse)
substitute the given values
[tex]cos(A)=\frac{9}{13}[/tex]
using a calculator
[tex]A=cos^{-1}(\frac{9}{13})=46.2^o[/tex]