1. The cross product of two vectors gives a vector perpendicular to both vectors, with magnitude equal to the area of the parallelogram formed by the two vectors.
2. If two adjacent sides of a parallelogram are given by vectors a and b, the area of the parallelogram is |a x b|.
3. If the position vectors of three vertices of a triangle are given, the area of the triangle can be found as 1/2 times the magnitude of the cross product of any two sides of the triangle.