How can I find the area of the triangle? (using sin/cosine/tan)

Erin writes the set of ordered pairs below. the set represents a function. {(3, –3), (5, 0), (–1, 4), (–6, 7)} erin claims that she can add any point to the set and have the set still represent a function. which of the following points can be used to show that erin's claim is incorrect? select three that apply. (–6, 1) (–1, 9) (0, 5) (1, 7) (3, –2)