Answer: A) sin 59° = cos 31°
Explanation:
Based on the angle and the sides provided, we can establish that
tan 31° = 17/x
Since no hypotenuse is provided and we cannot solve for it, we can rule out options B, C, and D.
We know that the sum of the angles of a triangle is 180°. In a right triangle, we know that one of the angles is 90°, so the other two angles are complimentary --> sin Ф = cos (90 - Ф).
Therefore, option A is true.