Final answer:
The correct equation is c) sin xº = opposite / hypotenuse, which defines the sine of an angle in a right triangle as the ratio of the length of the opposite side to the hypotenuse.
Step-by-step explanation:
The correct trigonometric equation that represents the relationship between the sides of a right triangle and an angle is c) sin xº = opposite / hypotenuse. This equation applies to any right-angled triangle, where 'sin' stands for the sine function, 'xº' is the angle in degrees, the opposite side is the side opposite to the angle xº, and the hypotenuse is the longest side of a right triangle, opposite the right angle. Thus, the sine of an angle is the ratio of the length of the side opposite to the angle (y) to the length of the hypotenuse (h).
Additionally, the other trigonometric functions, cosine (cos) and tangent (tan), are defined as follows: cos xº = adjacent / hypotenuse, where the adjacent side is the side next to the angle xº (excluding the hypotenuse), and tan xº = opposite / adjacent respectively. So for the given equations, options a), b), and d) are incorrect.