Answer:
22
Explanation:
The problem can be solved geometrically. By this way, the solution is going to be easy, as well.
We can see from the attached graph that the coordinates are the vertexes.
Considering a unit distance, we can find that the width of this rectangle is:
4 = 12 - 8
and the length is:
7 = 6-(-1)
Then, the perimeter is P = (4+7)*2 = 22