From the image provided, we are working with a function $P(x)$ representing the perimeter of an equilateral triangle in terms of its side length $x$, measured in centimeters.

Step 1: Analyze the Problem

For an equilateral triangle:

• The perimeter $P$ is calculated as the sum of all three equal sides.
• Since all sides of the triangle are $x$, the perimeter $P(x)$ is: $P(x) = 3x$

Step 2: Complete the Table

Using $P(x) = 3x$, substitute the values of $x$ from the table to calculate $P(x)$:

1. For $x = 0$: $P(0) = 3(0) = 0$
2. For $x = 1$: $P(1) = 3(1) = 3$
3. For $x = 2$: $P(2) = 3(2) = 6$
4. For $x = 3$: $P(3) = 3(3) = 9$
5. For $x = 4$: $P(4) = 3(4) = 12$
6. For $x = 5$: $P(5) = 3(5) = 15$
7. For $x = 6$: $P(6) = 3(6) = 18$

Final Table