Answer :
Answer:
y = -27 when x = 9 and z = -3
Step-by-step explanation:
y = kxz is the joint variation where k is a constant
Substitute the knowns in to find k
-50 = k( -10)(5)
-50 = -50k
k = 1
y = xz
Now find y
y = 9*-3
y = -27 when x = 9 and z = -3