Perimeter: Apply the distance formula four times to get the measures of each of the sides then add them.
Distance formula:
where and are the coordinates of the given points.
Area: Construct either diagonal and use the distance formula to calculate the measure of that diagonal. Constructing the diagonal creates two triangles for which you now know the measures of all three sides. Using that information in Heron's Formula, you can calculate the area of each of the triangles. The sum of the two triangle areas is the area of the quadrilateral.
Heron's Formula:
Where , , and are the measures of the three sides and is the semi-perimeter defined as the perimeter divided by 2, to wit:
John
My calculator said it, I believe it, that settles it
