Step 3: x+x+13=17−x+x

A. Distributive property
B. Addition/Subtraction property
C. Multiplication/Division Property
D. Combine Like Terms

D. Combine Like Terms

Step 3: x + x + 13 = 17 - x + x

In this step, we need to identify the property that is being used.

Looking at the equation, we can see that x is being added to x, and 17 is being subtracted by x. We also have the numbers 13 and 17 on both sides of the equation.

To simplify this equation, we need to combine like terms.

Therefore, the correct answer is:

D. Combine Like Terms.

To solve the equation x + x + 13 = 17 - x + x, we need to simplify both sides of the equation and then apply the appropriate property to solve for x.

First, let's simplify both sides of the equation by combining like terms:

On the left side:
x + x + 13 becomes 2x + 13.

On the right side:
17 - x + x becomes 17.

Now, we have the simplified equation: 2x + 13 = 17.

To solve for x, we'll need to isolate the variable.

To do that, we will subtract 13 from both sides of the equation:
2x + 13 - 13 = 17 - 13
2x = 4

Lastly, we divide both sides of the equation by 2 to solve for x:
2x/2 = 4/2
x = 2

Therefore, the solution to the equation x + x + 13 = 17 - x + x is x = 2.

In this specific step, we combined like terms; therefore, the correct answer is D. Combine Like Terms.