Factor the Expression 3x²+x: Finding the Common Term

To solve this problem, we'll follow these steps:

• Step 1: Identify the common factor
• Step 2: Extract the common factor from the expression

Now, let's work through each step:
Step 1: Look at each term of the expression $3x^2 + x$. - The term $3x^2$ can be written as $3 \cdot x \cdot x$, and the term $x$ as $1 \cdot x$.
From both terms, $x$ is a factor, making it the greatest common factor (GCF).

Step 2: Factor out the GCF:
Rewriting the original expression by factoring out $x$, we have:

$x(3 \cdot x + 1)$

Therefore, the expression $3x^2 + x$ can be factored as $x(3 \cdot x + 1)$.

This corresponds to choice 4: $x(3 \cdot x + 1)$.