advertisement

How far apart are these points? In this lesson you will learn to use absolute value to find distances between points with the same x and y value by using a coordinate plane. Let’s Review The Coordinate Plane (5,3) x value (-2,-3) y value Let’s Review Absolute Value: The distance a number is from zero on the number line. |3| = 3 |-3| = 3 A Common Mistake Begin by moving along the y-axis first, and then along the x-axis when finding an ordered pair. (6,4) A Common Mistake Returning to the origin after plotting the x value, and then moving on the y-axis. (6,4) Core Lesson A (6,4) B (6,0) A 4 units B |4 – 0| = |4| = 4 OR |0 – 4| = |-4| = 4 Core Lesson C (5,-6) D (0,-6) 5 units C D |5 – 0| = |5| = 5 OR |0 – 5| = |-5| = 5 Core Lesson E (0,4) 6 units F (6,4) E F |0-6|= |-6| = 6 OR |6 – 0| = |6| = 6 In this lesson you have learned to use absolute value to find distances between points with the same x and y value by using a coordinate plane. Guided Practice What is the distance between the two coordinate pairs A (2,-3) and B (0,-3)? Use absolute value and the coordinate plane to solve the problem. Guided Practice What is the distance between the two coordinate pairs C (-5,0) and D (-5,-9)? Use absolute value and the coordinate plane to solve the problem. Extension Activities Dice Challenge: 1. Roll two dice and use the numbers as the x and y values in an ordered pair. Plot the point on a coordinate plane. 2. Create a point on the x or y-axis that creates a line with your original point. 3. Find the distance between the two points. Extension Activities Human Coordinate Plane: Create a large coordinate plane on the classroom floor using masking tape. Have one person stand at a point on either the x or y-axis. Have another person stand on the coordinate plane at a point that shares either the x or y value as the first person. Have the class find the distance between the two points. Quick Quiz Which of the following coordinate pairs has a distance that is 8 units long? a. (0,-4) (-4, -4) b. (-3,6) (-3, 0) c. (0,-5) (8, -5) Quick Quiz Which of the following coordinate pairs has an absolute value of -4? a. (0,-4) (-4, -4) b. (-3,6) (-3, 0) c. (0,-5) (8, -5)