The given proportional relationship is y = -5x.
Therefore the ratio
y/x = -5 = -5/1
If x changes by 1, then y/x = y/1 = -5.
This means that y changes by -5 when x changes by 1.
The ratio of vertical change is -5:1
The standard equation for a straight line is
y = m*x + c
where
m = the slope,
c = the y-intercept.
Therefore the given relationship is a straight line with a negative slope of -5. This means that y decreases as x increases.
Answer: C
-5:1
The graph decreases from left to right.
