if y varies directly

Question

If y varies directly as? x, and
y=7
when
x=6?,
find y when
x=18

Answer 1

Jessica, for a direct variation, we have to have a constant ratio., where y = kx.

 

If we play with that algebraically, then k = y/x.

 

In our problem, k = 7/6, right? 

 

Plug in 18. y = (7/6)(18) = 21.

 

Hope this helps!