Question

A triangular pyramid is cut by a plane. In which case is the cross section a quadrilateral?

when the plane is perpendicular to the base and passes through the apex


when the plane is parallel to the base of the pyramid


when the plane intersects the base and two lateral faces of the pyramid


when the plane intersects the base and all three lateral faces of the pyramid

??????? help please

Answer 1

@LegendarySadist

Answer 2

@Legends

Answer 3

@Hero

Answer 4

@rosy

Answer 5

can anybody help me :/

Answer 6

@GreatGuy

Answer 7

this is tricky..

Answer 8

In geometry, a diagram always helps.

Answer 9

I'll let you try the other two cases.