Correct. The total time y equals running time plus warm-up time. So $\displaystyle{y}={0.25}{x}+{0.5}\usepackage{cmbright}\Huge\$ hours if she runs x miles. Graph the line and find the x-coordinate when $\displaystyle{y}={3}\usepackage{cmbright}\Huge\$ . It is $\displaystyle{x}={10}\usepackage{cmbright}\Huge\$ . This tells you that if she has 3 hours, then she can run 10 miles.