Answer:
Lines BC and F represent perpendicular lines
Explanation:
we have
Line BC

the slope of the line BC is

Line F

the slope of the line F is

we know that
If two lines are perpendicular, then the product of their slopes is equal to -1
so

we have
-----> slope line BC
-----> slope line F
Find the product of their slopes

therefore
Lines BC and F represent perpendicular lines