Final answer:
To solve the variation equation JZ^(9), we need to use the formula z = k * (y/x). By plugging in the known values and solving for k, we can find the value of z when y = -7 and x = -11.
Step-by-step explanation:
To solve the variation equation, we can use the formula: z = k * (y/x). Given that z varies directly with y and inversely with x, we can set up the equation:
z = k * (y/x)
Using the given values of y = 10, x = 2, and z = 55, we can solve for k:
55 = k * (10/2)
55 = 5k
k = 55/5
k = 11
Now, we can solve for z when y = -7 and x = -11:
z = 11 * (-7/-11)
z = 77/11
z = 7