Solution
For this case we need to remember that the general equation for a line is given by:
y= mx+ b
Where m represent the slope and b the intercept
And we can find the slope with this formuala:
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2023/formulas/mathematics/high-school/78uaqhwt0aws3qfwxigaftpihnmb1gzxtp.png)
And we can use (50, 725) and (100,1325) and we have:
![m=(1325-725)/(100-50)=12](https://img.qammunity.org/2023/formulas/mathematics/college/lrsb7w7l5gexag2thclumwaxa892si3bj5.png)
And the intercept would be:
725 = 50*12 +b
b= 725 - 600
b= 125
and the equation would be given by:
y= 12 x + 125
And the y intercept represent the starting value of 125$ no matter the number of guests