What is the result of combining the expression 6m + 9n - 2m + 3n?

• A. 4m + 12n
• B. 8m + 12n
• C. 2m + 6n
• D. 4m + 6n

Answer: (A)

To combine the expression 6m + 9n - 2m + 3n, you first identify the like terms in the expression. Like terms are terms that contain the same variable raised to the same power.

In this expression, we can group the terms with the variable m and the terms with the variable n separately. The terms with m are 6m and -2m. When we combine these:

6m - 2m = (6 - 2)m = 4m.

Next, we look at the terms with n, which are 9n and 3n. When we combine these:

9n + 3n = (9 + 3)n = 12n.

Therefore, when we combine all the like terms, we get:

4m + 12n.

This gives us the final simplified expression. The result of the combination of the expression is indeed 4m + 12n, confirming that this option is correct.