Answer:
see explanation
Step-by-step explanation:
since y varies jointly as x and z , then the equation connecting them is
y = kxz ← k is the constant of variation
to find k , use the row x = 5, y = 52.5, z = 7
k = [tex]\frac{y}{xz}[/tex] = [tex]\frac{52.5}{5(7)}[/tex] = 1.5, hence
y = 1.5xz ← equation of variation
first row, to find y with x = 2, z = 4
y = 1.5 × 2 × 4 = 12
third row, to find z with x = 1.5, y = - 36
-36 = 1.5 × 1.5z
z = [tex]\frac{-36}{1.5(1.5)}[/tex] = - 16
fourth row, to find x with y = 1.38, z = 23
1.38 = 1.5 × 23x
x = [tex]\frac{1.38}{1.5(23)}[/tex] = 0.04
