Answer:
12.5 units²
Explanation:
Step 1: Draw a rectangle enclosing the shape and find it's perimeter.
The perimeter of a rectangle is all the sides added together.
P = 7 + 5 + 7 + 5 = 24 units².
Step 2: Determine the area of the triangles on the outside and add them together. There are 3.
Area of a triangle:
.
A = area
a = leg 1
b = leg 2
Triangle 1:

3 units²
Triangle 2:

3 units²
Triangle 3:

A = 2.5 units²
Step 3: Add them together and subtract the total from the perimeter of the rectangle.
Perimeter of rectangle - total area of triangles = perimeter of the shape in question.
24 - (3 + 3 + 2.5) = P
24 - 11.5 = P
12.5 = P
Now, there are other ways to do it, but this is the way I chose.
The answer is 12.5 units².
Now you're done!