Mark H. answered 11/15/19
Tutoring in Math and Science at all levels
I posted the answer about 12 hours ago:
To get the length of a line, use the Pythagorean Theorem. Plot the 2 given points. Unless they have the same x values---or the same y values--- the distance is the hypotenuse of a right triangle where one side is the x difference and the other side is the y difference.
In this case, the x difference is -9 + 1 = -8
and the y difference is -4 -2 = -6
We therefore have a 3:4:5 right triangle and the distance is 10
Thus the perimeter of the hexagon is 60.