Answer:
B) SAS
Step-by-step explanation:
The angles between the two known equal sides are called a vertical angle and are equal. Thus you know Side-Angle-Side proves congruency.

Step-by-step explanation:
The ratio cosine tell us that
- In a right angled triangle, the cosine of an angle is the side adjacent to the angle divided by the hypotenuse of the triangle.
In other words,

The side adjacent to angle a is 9. The hypotenuse is 41.
So

The answer would be 537 because if you add 500 and 37 it would be 537 so that is your answer.