what is the difference between the constants of proportionality of graphs a and b?

Explanation:

Step1: Find constant for Graph A

For proportional graphs, $y=kx$. Use point $(3,6)$: $k_A=\frac{6}{3}=2$

Step2: Find constant for Graph B

Use point $(5,5)$: $k_B=\frac{5}{5}=1$

Step3: Calculate the difference

Subtract the two constants: $k_A - k_B = 2 - 1$

Answer:

1