A student draws two different straight lines p and q on his notebook. He marks that they both pass through point P as well as point Q, where P=Q.
(a) Using logical reasoning, prove that it is impossible for p and q to be distinct lines under the given condition.
(b) If the student now asserts that p and q are in fact the same line, explain why this new assertion is always true, irrespective of the actual positions of P and Q.