We have a triangle with one side of length 9 cm and an angle of 55 degrees opposite side $x$. Side $y$ is adjacent to the 55-degree angle and is the hypotenuse of a right triangle where side $x$ is opposite the right angle. We are asked to determine the lengths of sides $x$ and $y$.
2025/3/10
1. Problem Description
We have a triangle with one side of length 9 cm and an angle of 55 degrees opposite side . Side is adjacent to the 55-degree angle and is the hypotenuse of a right triangle where side is opposite the right angle. We are asked to determine the lengths of sides and .
2. Solution Steps
Since the triangle with sides and is a right triangle, we can use trigonometric functions to relate the sides and the given angle.
We have the side opposite the angle and the side adjacent to the angle. Thus we can find y using the cosine rule in the larger triangle. Let the third angle be A. Then,
, therefore degrees.
Since we know the length of the side opposite to the 55 degree angle and we know that is 9, we can set up the following relationships:
Since , we have