Answer:
8
Step-by-step explanation:
Varies directly think y=kx
Varies indirectly think y=k/x
We have first option so y=kx
x=6 and y=15 means we have 15=k(6)
So k=15/6 or reducing gives=5/2
So we just found our constant of proportionality, this number never changes. It stays the same no matter what x or y they give you...
So the equation is y=5/2 *x
Now what is x if y=20
Plug in 20=5/2 *x
So x=20*2/5=40/5=8
