If #y# varies inversely as #x#, and #y = 3# when #x = 6#, what is #x# when #y=18#?

1 Answer
Apr 6, 2017

#x=1#

Explanation:

#y# varies inversely as #x# means that

#yprop1/x#

#implies y=k*1/x =k/x# where #k # is some constant.

to find #k#, substitute the given values #y=3# when #x=6#

#i.e. 3=k/6 implies k=3*6=18#

#therefore # the equation becomes:- #y=18/x#.

Now substituting #y=18# in this equation;

#18=18/x implies x=18/18 =1#

Hence #x=1# when #y=18#