Given:
Let time be the independent variable.
Let mile marker be the dependent variable.
On one highway, Gabriela noticed that they passed mile marker 123 at 1:00. She then saw that they reached mile marker 277 at 3:00 and Mr. Morales was driving at a constant speed.
The coordinates of the points on this line are (1,123) and (3,277)
We need to determine the slope of the line.
Slope of the line:
The slope of the line can be determined using the formula,
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/e9lgdayfzr27dyurvzbw9lffpiv7535tiv.png)
Substituting the points (1,123) and (3,277) in the above formula, we get;
![m=(277-123)/(3-2)](https://img.qammunity.org/2021/formulas/mathematics/high-school/243xbl5b69lkrq1rct6q6tzvjiqfv02i0h.png)
![m=(154)/(1)](https://img.qammunity.org/2021/formulas/mathematics/high-school/vt6q031k0jcd1xa68q1xi26ybyil25aj8o.png)
![m=154](https://img.qammunity.org/2021/formulas/mathematics/high-school/4qesrl63pdnd771z2ietfo1em9sw8krz2r.png)
Therefore, the value of the slope of this line is 154.