Goal (sport) the ball can be kicked either under the crossbar for a goal, or over the crossbar between the posts for a point. The vertical supports are usually called "goal posts" and the horizontal top is usually called the "crossbar". A goal in these games normally requires that the ball or puck be sent between the posts, under the crossbar and completely behind the goal line. In Australian rules football, there is no crossbar but four uprights instead. In netball, a single post at each end of the court supports a horizontal hoop that the ball must fall through. In basketball,
Five points determine a conic theorem. Similarly, while nine points determine a cubic, if the nine points lie on more than one cubic—i.e., they are the intersection of two cubics—then they are not in general position, and indeed satisfy an addition constraint, as stated in the Cayley–Bacharach theorem. Four points do not determine a conic, but rather a pencil, the 1-dimensional linear system of conics which all pass through the four points (formally, have the four points as base locus). Similarly, three points determine a 2-dimensional linear system (net), two points determine a 3-dimensional linear system (web), one point determines a 4-dimensional linear system, and