Calculate the perimeter of the parallelogram. Round to the nearest tenth, if necessary. Enter the perimeter, in units, using numbers only (decimal point is ok, if needed).

28 units

Step-by-step explanation:

Firstly, we can see that the vertical sides are 9 units each.

To get the diagonal sides, we can turn the ends into right triangles, which we can then use with the Pythagorean Theorum.

To make the top side into a triangle, we would draw a horizontal line connecting points (-1, 3) and (3, 3). This creates a right angle which is essential when using the Pythagorean Theorum.

A^2 + B^2 = C^2

We can plug in values for the Pythagorean Theorum because we can see that going across horizontally from point (-1, 3) to (3, 3), there are 4 units in between the two points. This will be our A value. We will do the same but vertically from points (3, 6) to (3, 3). The 3 units between the two points will be our B value. Now, we can plug in our values into the Pythagorean Theorum to find side C, the hypotenuse.

4^2 + 3^2 = C^2

16 + 9 = C^2

25 = C^2

√25 = C

C = 5

Now that we know the diagonal value of the side, we also know the same diagonal value of the bottom side. When you add all four sides together,

9 + 5 + 9 + 5 = 28

you get 28, which is the perimeter of the parallelogram.