The constant propertion is the slope of the line
The expression for the constant proportion is :
[tex]\text{ Constant Proportion:}\frac{y}{x}\text{=}\frac{y_2-y_1}{x_2-x_1}[/tex]Consider any two coordinates of the graph : ( 1, 10) & (2, 20)
[tex]\begin{gathered} \text{ Constant Proportion:}\frac{y}{x}\text{=}\frac{y_2-y_1}{x_2-x_1} \\ \text{Constant Proportion:}\frac{y}{x}\text{=}\frac{20-10}{2-1} \\ \text{Constant Proportion:}\frac{y}{x}\text{=}\frac{10}{1} \\ \text{Constant Proportion:}\frac{y}{x}\text{=}10 \\ \text{ Apply crossmultiplication } \\ \frac{y}{x}=\frac{10}{1} \\ y\times1=10\times x \\ y=10x \end{gathered}[/tex]So the equation is y = 10x
Answer : y = 10x
