y = kxz
8 = k(-2)(4)
8 = -8k
k = -1
y = -3x
12 = -3x
x = -4
Answer is A
Suppose y varies jointly with x and z, and x = 4 when y = 8 and z = -2.What is the value of x when y = 12 and z = 3?
A. -4
B. 4
C. 15
D. 9
1 answer