Question

What function is quadratic?

a) y=x(3x+2)
b) x-5y=9
c)y=5x-2
d)y=x3+2x2

Answer 1

i dont know

Answer 2

quadratic function is in the form of
\(\large\color{black}{ \displaystyle y=\color{red}{ a}{\rm x}^2+\color{green}{ b}{\rm x}+ \color{blue}{ c} }\)


Where \(\large\color{black}{ \displaystyle \color{red}{ a} }\) , \(\large\color{black}{ \displaystyle \color{green}{ b} }\) and \(\large\color{black}{ \displaystyle \color{blue}{ c} }\) are just numbers.

\(\large\color{black}{ \displaystyle \color{green}{ b} }\) and \(\large\color{black}{ \displaystyle \color{blue}{ c} }\) could be any positive/negative number or zero.
And, \(\large\color{black}{ \displaystyle \color{red}{ a}\ne0 }\)

Answer 3

expand all of the choices, and see which one is like
\(\large\color{black}{ \displaystyle \large\color{black}{ \displaystyle y=\color{red}{ a}{\rm x}^2~~... } }\)