The expression 9b + 21 factored using the GCF is 3(3b+7).
How to factor the algebra expression?
The given algebraic expression is seen as;
9b + 21
The greatest common factor (GCF) of 9 and 21 is 3, which can be used to factor the expression.
This can be shown as follows:
= (3 × 3b) + (3×7)
=3(3b+7)
Therefore, the expression 9b+21 factored using the GCF is 3(3b+7)