1. The problem statement, all variables and given/known data Find the area of triangle with vertices (-2,-2,2,2), (0,0,1,-1), (-1,-2,1,1) 2. Relevant equations 3. The attempt at a solution The only way I know how to find the area of a triangle is by finding half the parallelogram. I.e. A = (1/2)||u x v|| But this requires cross product and you can't find the cross product in 4-space, can you? Any help/explaination would be greatly appreciated.