Suppose y varies jointly with x and z, and y = 12 when x = 5 and z = 2. Find y when x = 10 and z = -3

Answer 1

y = kxz

12 = k5(2) = 10k

k = 12/10 or 6/5

y = (6/5)xz

y = (6/5)(10)(-3)

y = -180/5

y = -36