Question

Is two distinct planes that intersect always intersect in a line, is it true or false

Answer 1

true.
@itamar

Answer 2

true

Answer 3

Can you tell me how @Loser66 @MikuxLuka

Answer 4

That's actually the definition of a line: the intersection of two planes...if they intersect!

Answer 5

Thanks so much @mathmate

Answer 6

If two planes intersect, their intersection consists of at least one point. On this point you can draw two lines (A and B) perpendicular two each of the planes, and since the planes are different, the lines are different as well. All points on the line perpendicular to both lines (A and B) will be on a single line (C), and this line, going through the interesection point will lie on both planes.

Answer 7

You're welcome! :)