If f(x) varies directly with [tex]x^2[/tex]
If f(x) varies directly with x then we use equation f(x) = kx
where k is the constant of proportionality
So equation becomes [tex]f(x) = kx^2[/tex]
We use the information and find out k
f(x)= 10
[tex]f(x) = kx^2[/tex]
[tex]10= kx^2[/tex]
[tex]k = \frac{10}{x^2}[/tex]
now we use the value of k and find the value of f(x) when x=3
[tex]f(x) = \frac{10}{x^2}*x^2[/tex]
f(x) = 10
The value of f(x) = 10 when x= 3
