Answer:
[tex]m=2,000\text{ / month}[/tex]Explanation: We have to find the average rate of change in price per month, this problem can be modeled by using the standard equation of the line:
[tex]y(x)=mx+b[/tex]Where y(x) is the house cost as a function of the month and the "m" is defined as follows:
[tex]m=\frac{\Delta y}{\Delta x}\Rightarrow(1)[/tex]In other words, m is the change in house cost over the change in the months:
[tex]m=\frac{\Delta y}{\Delta x}=\frac{276000-240000}{18-0}=\frac{36000}{18}=2000[/tex]Conclusion: Therefore the average change in the cost per month is as follows;
[tex]m=2000\text{ /month}[/tex]The standard equation that can model it is as follows:
[tex]\begin{gathered} y(x)=2000x+0 \\ b=0 \\ y(x)=2000x \end{gathered}[/tex]