Answer:
[tex]0.3[/tex]
Step-by-step explanation:
we can find slope of the line using the formula,
[tex]m = \frac{ (y₂ - y₁) }{ (x₂ - x₁) } \\ m = \frac{6 - 1.5}{20 - 5} = \frac{4.5}{15} = 0.3[/tex]
The constant of proportionality, which is also the slope of the line, is 0.3.
