Answer:
9.3 centimeters
Step-by-step explanation:
If the length of the third side of the triangle is c, then according to the Law of Cosines, c2 = 72 + 132 – 2(7)(13)(cos 44°). The value of c2 can be simplified to approximately 49 + 169 – 130.9198, or 87.0802, using a calculator. By taking the square root of 87.0802, the length of the third side of the triangle comes out to be approximately 9.3 centimeters.
For this case we have to, by definition:

This means that the tangent of angle B will be equal to the leg opposite the angle on the leg adjacent to the same angle.
Then, clearing to have:

Rounding out the value of a we have:

Answer:
Option C
It’s A
As it says in the answer, you usually add / subtract the exponents when needed.