Conjecture: When one plane intersects another plane, the intersection of the two planes is a line.

Question

Intersecting planes

Is this conjecture true?

No, planes never intersect.

No, when two planes intersect, the intersection is a curve, never a straight line.

Yes.

No, when two planes intersect, the intersection is a line segment, never a line.

Answer 1

The conjecture is true: when one plane intersects another plane, the intersection of the two planes is indeed a line.

So the correct response is:

Yes.