While I can't be 100% sure, I believe that this is how you would solve this problem: x=7, and y=14. As y varies directly as x, y=2(x), seen through 2(7)=14. Therefore, when x=10, y=2(10)=20 And so, y= 20.
Just for terminology: y varies directly with x... [tex]y = kx[/tex] y varies directly with x²... [tex]y = kx²[/tex] y varies indirectly with x...[tex]y = k/x[/tex]
We need to find the constant [tex]k[/tex] in the equation [tex]y=kx[/tex].
Plug in the known values. [tex]14=k\dot7[/tex]...[tex]k=2[/tex].
