To solve the system of equations:

1) x/3 = y/4

Cross multiplying, we get:

4x = 3y

2) x * y = 432

Now, we can substitute the value of 4x from equation 1 into equation 2:

(4x) * y = 432

4xy = 432

Dividing both sides by 4:

xy = 108

Now, we can substitute the value of xy into equation 1:

4x = 3y

4x = 3(108)

4x = 324

Dividing both sides by 4:

x = 81

Substituting the value of x into equation 2:

81 * y = 432

Dividing both sides by 81:

y = 432/81

y = 5.33

Therefore, the solution to the system of equations is x = 81 and y = 5.33.