Question

How do you know if a function is quadratic??

Answer 1

F(x) = y = ax^2 + bx + c is the equation, where a, b, and c are numbers and a is not equal to zero. If it was zero, then the equation would be linear and not quadratic. For example, if you have f(x) = x +9 + 4x^2, you would rewrite the function with the largest exponent first, so you would have f(x) = 4x^2 + x + 9.

Answer 2

Usually it's in standard form: ax²+bx+c

or vertex form: y=a(x-h)²+k

If you put the graph into a graphing calculator it's going to look like a hill/depression.

Explanation:

Standard form ex: 3x²+2x+1

Vertex form ex: y=4(x-1)²-2