Answer:
Step-by-step explanation:
Write the prime factors making up the two expressions
48x^2: 2 * 2 * 2 * 2 * 3 * x * x
32x^3: 2 * 2 * 2 * 2 * 2 * x * x * x
Underline what is common to both
The highest common factor is 2 * 2 * 2 * 2 * x * x
The highest common factor is 16x^2
This may look very simplistic, but try a question like this
5397691 and 3271021
The method I've shown you is likely the only way you could factor these two monsters and they are relatively small numbers.