Factoring Polynomials: How to Factor 20x^4 + 45x^5

Published on March 31, 2026

Algebra

Learn how to factor the expression 20x^4 + 45x^5 by identifying and extracting the greatest common factor of 5x^4, resulting in the expression 5x^4(4 + 9x).

Question

Factor the expression completely. 20, x, to the power 4 , plus, 45, x, to the power 5 20x 4 +45x 5

Answer

To factor the expression completely, follow these steps:
Step 1: Identify the greatest common factor (GCF) of the numerical coefficients.
The coefficients are and .
  • The factors of are .
  • The factors of are .
    The greatest common factor of and is .
Step 2: Identify the greatest common factor of the variable terms.
The variable terms are and . The GCF of powers of the same variable is the variable raised to the lowest exponent present in the expression.
The GCF of and is .
Step 3: Combine the GCF of the coefficients and the variables.
The overall GCF of the expression is .
Step 4: Factor out the GCF.
Divide each term in the original expression by :
Write the expression as the product of the GCF and the remaining polynomial:
The expression is now factored completely.