Answer:
13.51
Explanation:
From the question,
z(square) is directly proportional to x(cube)
Z^2 ∝. X^3
Z^2=kX^3
Where K = proportionality constant
Making K the subject of the formula
K=Z^2/X^3
K=(8^2)/(4^3)=16/64
K= 16/64
Then find the values of z when x = 9.
From aboveZ^2=kX^3
Z^2= 16/64 × (9^3)
=16/64 × 729
Z^2=182.5
Z=√182.5
Z=13.51