Fill in the blank.

A pair of intersecting planes ________ intersect in exactly one point.

A- always

B- sometimes

C- never

D- not enough information

My choice is C.

C is correct. Intersecting planes intersect at a single line, not point.

Thanks!! :)

Correct! A pair of intersecting planes never intersect in exactly one point. This is because two planes can intersect in a line, not just a single point. To understand this, imagine two pieces of paper intersecting each other at an angle. The line where they intersect represents the intersection of the two planes. Therefore, two planes can intersect in more than one point, but never in exactly one point.