SOLUTION: The square of y varies inversely as x and directly as z. If y = 3 when x = 12 and z = 21, find y when x = 8 and z = 28.

Algebra ->  Systems-of-equations -> SOLUTION: The square of y varies inversely as x and directly as z. If y = 3 when x = 12 and z = 21, find y when x = 8 and z = 28.      Log On


   

Question 586261: The square of y varies inversely as x and directly as z. If y = 3 when x = 12 and z = 21, find y when x = 8 and z = 28.
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
x * y^2 = k * z

12 * 3^2 = k * 21 ___ (12 * 9) / 21 = k ___ 36/7 = k

8 * y^2 = (36/7) * 28