Chapter 7 - Polynomial Equations and Factoring - 7.4 - Solving Polynomial Equations in Factored Form - Exercises - Page 381: 28

$10x^2(2x+3)$.

The given expression is $=20x^3+30x^2$ The GCF of $20$ and $30$ is $10$. The GCF of $x^3$ and $x^2$ is $x^2$. So, the greatest common monomial factor of the terms is $10x^2$. Hence, the factor form is $10x^2(2x+3)$.