Answer :
Direct variation:
[tex]\sf~y=kx[/tex]
Plug in what we know:
[tex]\sf~9=k(5)[/tex]
[tex]\sf~9=5k[/tex]
Divide 5 to both sides:
[tex]\sf~k=\boxed{\sf1.8}[/tex]
So the constant of variation is 1.8.
[tex]\sf~y=kx[/tex]
Plug in what we know:
[tex]\sf~9=k(5)[/tex]
[tex]\sf~9=5k[/tex]
Divide 5 to both sides:
[tex]\sf~k=\boxed{\sf1.8}[/tex]
So the constant of variation is 1.8.