Question

z varies jointly as x and y and inversely as w. Write the appropriate combined-variation equation, and find z for the given values of x, y and w.

z = 10 when x = 5, y = -2 and w = 3; x = 8, y = 6 and w = -12

Answer 1

those are the answers btw

Answer 2

it is the 4 option

Answer 3

z= kxy/w
then replace to find k
10 =k(5)(-2)/3