SOLUTION: I am not sure if this is the right place to post this one, but here goes. A variable z varies jointly with x and the square of y. If z=6 when x=4 and y=3, write the equation o

Algebra ->  Coordinate-system -> SOLUTION: I am not sure if this is the right place to post this one, but here goes. A variable z varies jointly with x and the square of y. If z=6 when x=4 and y=3, write the equation o      Log On


   



Question 385125: I am not sure if this is the right place to post this one, but here goes.
A variable z varies jointly with x and the square of y. If z=6 when x=4 and y=3, write the equation of joint variation.
Thanks for the help. I am so lost in this class.
Karen

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A variable z varies jointly with x and the square of y.
:
Write this: z = k*x*y^2; (k = the constant of variation)
:
If z=6 when x=4 and y=3, write the equation of joint variation.
Find k using these values
6 = k*4*3^2
6 = 36k
k = 6%2F36
k = 1%2F6
:
The equation of joint variation:
z = 1%2F6*x*y^2
:
:
You can check this: substitute 4 for x and 3 for y, ensure that z = 6