Title: Lesson 3-6
Author: mark_cameron
Last saved by: MHE
Company: McGraw-Hill

Lesson 3-7

EXAMPLES    Name an Ordered Pair
1. Name the ordered pair for point H.

•	Start at the origin.
•	Move right to find the x-coordinate of point H, which is 4.
•	Move up to find the y-coordinate, which is 3.

So, the ordered pair for point H is (4, 3).

2. Name the ordered pair for point M.

•	Start at the origin.
•	Move left to find the x-coordinate of point M, which is .
•	Move down to find the y-coordinate, which is .

So, the ordered pair for point M is .

EXAMPLES    Graphing Ordered Pairs
Graph and label point each point. 
3.  A
•	Start at the origin and move  units to the right. The move up  units.
•	Draw a dot and label it A.

4.  B(–3, –2.5)
•	Start at the origin and move 3 units to the left. The move down 2.5 units.
•	Draw a dot and label it B(–3, –2.5).

 

Example 5 Find Distance on the Coordinate Plane
Graph the ordered pairs (2, 0) and (6, −3). Then find the distance between the points.

   			Pythagorean Theorem
   			Replace a with 4 and b with 3.
   			4^2 + 3^2 = 25
			Definition of square root
      c	= 5			Simplify.

The points are 5 units apart.

Example 6 Real-World Example
MAPS On a map, Callie’s house is located at the point (−3, 5) and Aaron’s house is located at the point (4, 2). A unit on the map is equal to 0.05 mile. Find the distance between Callie’s house and Aaron’s house.

Let c represent the distance between Callie’s house and Aaron’s house. Then a = 3 and b = 7.
   			Pythagorean Theorem
   			Replace a with 3 and b with 7.
   			3^2 + 7^2 = 58
			Take the square root of each side.
      c ≈ 7.6			Simplify.

The houses are about 7.6 units apart. Since each unit equals 0.05 mile, the distance between the two houses is about 0.05 ∙ 7.6 or 0.38 mile.