//You can substitute some values in to find out, for example (1, -5) and (5, -5) are good.
Using this method, you can deduce that it would be A
Answer:
yes it is and its also a coordinate
Step-by-step explanation:
c^2 = a^2 + b^2 - 2(ab)(cos C)
c^2 + 2(ab)(cos C) = a^2 + b^2
2(ab)(cos C) = a^2 + b^2 - c^2
cos C = (a^2 + b^2 - c^2) / 2ab - Answer choice E
Hope this helps! :)