If two lines are perpendicular, their slopes are negative reciprocals.

true

Step-by-step explanation:

yes, that is true.  Parallel lines have equal slopes and perpendicular lines have negative reciprocal slopes (or opposite reciprocals, the "opposite" being the sign).

For this case we have by definition, that if two lines are perpendicular then the product of their slopes is -1. That is to say:

This means that the slopes are negative reciprocals.

The statement is true

The first quotient 12 means there are 12 group of students each group having 5

The second means there are 5 groups each having 12 students