This graph shows a proportional relationship.
What is the constant of proportionality?

Step-by-step explanation:

Given

See attachment

Required

The constant of proportionality

Select two points on the graph

So, the constant of proportionality (k) is:

step-by-step explanation:

we have

using a graphing tool

see the attached figure

this is a quadratic equation (vertical parabola) open up

the vertex is a > vertex

the domain of the function is all real > interval (-∞,∞)

the range of the function is the > [-6.125,∞)

the function has two x->   and

the function is increasing over the > (0.25,∞)

the function is decreasing over the > (-∞,0.25)