Answer: option D
Step-by-step explanation:
Remember the cosine identity:

Given the right triangle DFE shown in the image, you can identify that the adjacent side and the hypotenuse for the angle F of this triangle are:

Now you can substitute values into
and then reduce the fraction.
THerefore you get:
Answer:
(-2, 5)
Step-by-step explanation:
A reflection across the origin turns the point (a, b) into (-a, -b).
The quotients are equal because they both go in the same number of times. The second pair of quotients just have an extra 0 at the end which just changes the place value of the number.