Question

Write true (T) or false (F) for the following statement:

 If a² ends in 9, then a³ ends in 7.

Answer 1

 False
a³ ends in 7 if a ends with 3.
But for every a² ending in 9, it is not necessary that a is 3.
E.g., 49 is a square of 7 and cube of 7 is 343.