How do you spell 725, 213

What term best describes a line ans a point that lie in the same plane

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?

Pranza plotted point a in the coordinate plane below.