Question

Which is the quadratic variation equation for the relationship?

Answer 1

$y=kx^2 \\ \\ y=36 \hbox{ when } x=3 \\ 36=k \times 3^2 \\ 36=k \times 9 \\ k=4 \\ \\ \boxed{y=4x^2} \Leftarrow \hbox{answer B}$