Respuesta :

Brainliest of I helped : )
Here: Remember f(x) is the same thing as y. 
Quadratic functions are y=x^2.
So you could literally add anything to it and make it another function. E.g. f(x)=x^2 + 1
You could just keep adding another value to the second term like x^2 + 2.
But if you want functions here you go: 

x^2 -3x -4
x^2 +9x +8
x^2
x^2 +1
x^2 -3x -10
x^2 + 2x
2x^2 
3x^2
4x^2

How do you graph them? Easy just choose an x value, like 0 or 1 or 7 or -5, and plug it into the equation. If you had f(x)=x^2 then it's just 5^2, 25. So when x is 5, f(x)  [y is f(x)] is 25. Likewise you would plug it into 2x^2 and get 2 (5^2). When x is 5, f(x) is 50.... 2(25)= 50