Factor out the GCF of \(21x^3+24x^2-12x\)
Take a look at the coefficients. Think about their prime factorization.
Each of these has 3 as a factor, so that can be taken out.
\(3(7x^3+8x^2-4x)\)
Looking now at the variables, you might notice each has x as a factor.
Let's take that out.
We are left with our final answer \(\boxed{3x(7x^2+8x-4)}\)
