Corollary: If two intersecting lines in one plane are parallel to two intersecting lines in the other plane, then

the two planes are are parallel.

Another theorem for parallel planes:

Two planes perpendicular to the same line are parallel.

If two intersecting lines in a plane are parallel to another plane, then the two planes are parallel...If there is no common *** point across the two planes then the two planes are parallel to each other

If two intersecting lines in a plane are parallel to another plane, then the two planes are parallel. If two intersecting lines in one plane are parallel to two intersecting lines in another plane, then the two planes are parallel. If two parallel planes intersect a third plane at the same time, then their intersections are parallel.