FAN AND MEDAL!!!

In a direct variation, y is 9 when x is eighteen. What is y when x equals six?

Question

FAN AND MEDAL!!! 

In a direct variation, y is 9 when x is eighteen. What is y when x equals six?

anonymous · Answer

y is 3 here...

imstuck · Answer

Do you know how to set up these types of problems?  with a K?

anonymous · Answer

nope

imstuck · Answer

Giving an answer doesn't help the learning process.

anonymous · Answer

yea bro

imstuck · Answer

Ok, in a direct variation problem the set up is y = kx.  They tell you that y = 9 when x = 18.  So let's fill that in:  9 = 18k.  Solving for k we get 1/2.  K = 1/2.  Now use that value of k in the next part of the problem.

imstuck · Answer

What is y when x = 6?  Going back to our variation equation y = kx we need to solve for y when x = 6 and we have solved for k.  Solve y = kx when k = 1/2 and x = 6.  $$y=\frac{ 1 }{ 2 }(6)$$What is one-half of 6?