Answer:6
Step-by-step explanation:
Area of triangle = 0.5(width*height)
If you put 0 in the place of x or y, which every one you choose, it will cancel it or and you can just divide the number next to it by the answer (-20, 20). Take it one step at a time, don't try to do both at the same time.
Beatrice is incorrect. All of these points are not on the same line because the slope between (-2 , -1) and (1, 0), which are coordinates from each of these pairs above are not equal to 1/2