A Quadrilateral

Question

Quadrilateral PQRS has vertices P(3, 2), Q(0, 4), R(-2, 1) and S(1, -1) ?: 
a) Verify that quadrilateral PQRS is a square.
b) Find the perimeter of the rectangle.

Answer 1

Find the distance between point P and point Q.

"      "    distance between point Q and point R.

"      "    distance between point R and point S.

"      "    distance between point S and point P.

 

Then add those distances to get the perimeter.  It is a square if the 4 distances are the same, and each pair of lines are perpendicular to each other.  Perpendicular means the intersecting lines have negative reciprocal slopes.