When you are solving inequality for a rational function you don't do it the same way as you would solve an equality. Now the instructor shows how to solve an inequality with the help of an example. Now to solve an inequality which is in the form a/b first take the numerator and denominator as separate equations of two lines. Now graph the two lines on coordinate axes. Using the graphs of the lines plot the intercepts of the equations on the number line noting down the sings. Now you can compare both the number lines making sign charts and solve the equations easily as shown in the video. This video shows how to solve inequalities using sign charts.