Answer:
B. 7 cm
Step-by-step explanation:
Two angles are said to be supplementary if their sum is 180 degrees. So, if x and y are supplementary angles, the formula is

We know that one of the angles (say x) is 98. So, the equation updates to

If we want to solve for the other angle, we can simply subtract 98 from both sides to get

The Pythagorean trigonometric identity is a trigonometric identity expressing the Pythagorean theorem in terms of trigonometric functions. Along with the sum-of-angles formulae, it is one of the basic relations between the sine and cosine functions.
Answer:
9
Step-by-step explanation: