In the figure above, sin a = x. What is the value of cos b?
A. x
B.
C. |1 - x|
D.
Answer:A
In the figure above, sin a = x. What is the value of cos b?
A. x B. C. |1 - x| D.
Explanation: A You can plug in when you're dealing with a geometry problem with unknowns. When you're Plugging In for a right triangle, use one of the special right triangles to make your life easier. Use a 3-4-5 right triangle. Make the side opposite a 3, the side adjacent to a 4, and the hypotenuse 5. Because sine is , sin a = , so x = . Cosine is , so cosb = . This is your target; circle it. Make x = in each answer choice and look for the answer which equals . Only (A) works.