Question 146362
the standard form of a quadratric equation  is ax^2 + bx + c = 0.

given equation is 4x^2 + 20x = 0.

here equation is having only two terms, x^2 & x term. there is no constant term , i.e. c =0.
we can write the equation as 4x^2 + 20x + 0 =0 ( instead of writing like this zero is avoided , since it makes no sense)

comparing with standard form , we get  a= 4 , b = 20 & c= 0.