We can clearly see a line ‘a’ whose equation is lx + my = n. We also see p which is the length of the perpendicular on the line from the origin and α which is the angle made by this perpendicular with the positive x -axis.
As we change the values of α and p using their corresponding slide bars, we can observe how the position of the line changes.

Questions to think about
Fix the value of α and change the value of p. What do we observe?
Fix the value of p and change the value of α. What do we observe?
Input values for cos α, sin α and p in the equation x cos〖α+y sinα 〗=p and compare the result with the given equation of ‘a’ which is lx + my = n