The equation is .

Add 20x to each side.

Compare the equation with .

a = 4, b = 20 and c = 25

a) Now we can find discriminant value

     (Substitute a = 4, b = 20 and c = 25)

= 0                                             (Simplify)

b) The discriminant is positive, so the equation have two rational roots.

c) Apply quadratic formula:

        (Replace , a with 4, and b with 20)

The solution is .

The discriminant value is 0 and the equation have one rational root.

The solution is .