1. 1.4 Perimeter and Area in the Coordinate Plane

2. Get some graph paper! Draw an label and x and y axis.
Draw quadrilateral ABCD where A(1,4),
B(-3,1) C(0, -3) and D(4, 0) .

3. 3) Are the adjacent sides of the quadrilateral ABCD perpendicular to each other? How can you tell?

4. Pop Quiz
Turn over your graph paper and write the following:
P A

6. Back to our graph….
4) What is the perimeter of quadrilateral ABCD? 5) Is ABCD a square? Why or why not? 6) Find the area of ABCD.

7. 7) Partition ABCD into four right triangles and one square
7) Partition ABCD into four right triangles and one square. 8) After checking that your partitioned correctly, find the area of each triangle and the square. 9) Is the sum of the areas of the 5 polygons equal to the area of the larger polygon? Does this make sense?

8. Window partners – communicate to your wall partner the steps on finding the perimeter of a polygon in the coordinate plane. Be specific.

9. Wall Partners – communicate to your window partner on how to find the distance between two points on the coordinate plane.

10. Definition
Polygon – A closed figure in a plane formed by three or more line segments (called _____). Each segment intersects exactly two segments. The intersection is called a ______. No two ______ with a common vertex are collinear. You can name a polygon by listing the _______ in consecutive order.

11. Classifying Polygons

12. Convex – when no line that contains a side of the polygon contains a point in the interior of the polygon. Concave – when a line that contains a side of the polygon contains a point in the interior of the polygon.

13. Guided Practice – To be handed in
Find the perimeter and area of the polygons with the following vertices.
B(2,4) U(2,-3) M(-2,-3) P(-2,4)
E(-4,8) L(6,8) I(6,-8)
C(-20,10) R(30, 10) U(30, -10) Z(-20, -10)