I do not know how to do it

The solution set for 5v2 – 125 = 0 is

David is spreading mulch on a triangular area of his flower bed. the coordinates of the vertices of the area are (1, 3), (9, 3), and (4, 6). what is the area of the triangle if each square has an area of 3 square feet?

Which of the following parabolas opens down?