Add up the lengths of the several sides of the polygon.
Examples: The perimeter of a triangle is the sum of the lengths of the 3 sides.
The perimeter of a hexagon is the sum of the lengths of the 6 sides.
And so on.
I highly recommend drawing any polygon whose perimeter you wish to calculate.
Answer:
-1
Step-by-step explanation:
m = y2 - y1 / x2 - x1
= 1 - 4 / 8 - 5
= -3 / 3
= -1