The answer is below.
Work Step by Step
In order to graph the equation, first isolate y on one side of the equation: $$y=(-1.25/4.2)x+(28.7/4.2)$$ Next, enter the equation into the calculator under $Y_1$. Finally, hit the graph key to view the graph. **Note, press the "window" key on the calculator to view and change the window.