Answer:
If y varies jointly as x^2 and z, we can write the equation as y = k * x^2 * z, where k is the constant of variation.
To find the constant of variation, we can use the given values of y, x, and z:
y = 225, x = 3, and z = 4
Substituting these values into the equation, we get:
225 = k * 3^2 * 4
225 = k * 36
Solving for k, we get:
k = 225/36
k = 6.25
Therefore, the constant of variation is 6.25.