+0  
 
0
22
1
avatar

The variable x varies directly as the square of y, and y varies directly as the cube of z. If x equals -16 when z equals 2, what is the value of x when z equals 1/2?

 
 Jan 11, 2019
 #1
avatar+15327 
+2

x = k y^2     and y = kz^3     where k = some constant

   we can combine the constants and sub z^3 in for y

x = k (z^3)^2 = k z^6        now sub in x = -16   and z = 2

-16 = k (2)^6

k = -1/4 

 

so the equation becomes   x = -1/4 z^6      NOW, sub in z = 1/2

                                           x = -1/4 (1/2)^6 = - 1/256

 
 Jan 11, 2019

36 Online Users

avatar
avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.