A quadratic function is any function that can be written in the form: y = ax^2 + bx + c ;
where a, b, and c are real numbers and a = 0 A/ expression doesn't have x^2, so it's wrong B/ y = (x-5)^2 = x^2 - 2.5.x + 5^2 = x^2 - 10x + 25 <=> y = x^2 - 10x + 25 So B is quadratic function As for C and D they're not quadratic functions
