Are four planes are coplanar

Four planes are not necessarily coplanar. For four planes to be coplanar, they must all intersect along a common line or within the same two-dimensional space. In general, three planes can intersect at a single point or line, but adding a fourth plane may cause it to not share the same intersection, thus not being coplanar. Therefore, unless specific conditions are met, four planes typically do not lie in the same plane.