Answer:
The slope of FG is -1
Explanation:
Given
Square EFGH
EF:

Required
Determine the slope of FG
First, we calculate the slope of EF

Make y the subject


The general equation has the form:

Where

Compare
to


From the name of the square EFGH, we can conclude that EF and FG are perpendicular
The relationship between perpendicular lines is:

Where
-- Slope of EF
and
m2 = slope of FG
Substitute 1 for m1 in



Hence, the slope of FG is -1