SOLUTION: What is the perimeter of triangle PQR with vertices P(-2,9), Q(7,-3), and R(-2,-3) in the coordinate plane?
21 units
25 units
34 units
36 units
Question 653857: What is the perimeter of triangle PQR with vertices P(-2,9), Q(7,-3), and R(-2,-3) in the coordinate plane?
21 units
25 units
34 units
36 units Answer by solver91311(24713) (Show Source):
One of the sides of the triangle is vertical, so the length of that side is just the difference of the coordinates.
One of the sides is horizontal, so the length of that side is just the difference of the -coordinates.
In order to tell which points are on the horizontal side and which are on the vertical side, use the following facts: Points on a horizontal line have equal -coordinates. Points on a vertical line have equal -coordinates.
To determine the measure of the third side, you need the distance formula:
where and are the coordinates of the given points.
Once you have the measures of all three sides, add them to get the perimeter.
John
My calculator said it, I believe it, that settles it
