Performance Task #1 This activity is adapted from the Light it up activity from the National Council of Teachers Mathematics (NTCM) illumination project. http://illuminations.nctm.org/Lesson.aspx?id=1968 Materials: Flashlight with narrow beam or laser pointer. (LED flashlights may not be suitable for this activity) Flat mirror Measuring tape or meterstick . A thick book Instructions: 1. Place the thick book a short distance from the wall and place the mirror on top of the book. 2. Stand on the side of the mirror opposite the wall. Aim the flashlight toward the center of the mirror so that the light reflects off the mirror and onto the wall. 3. Take the following measurements in centimeters and note down the values: (A) a = the height of the flashlight from the floor (B) b = the distance between the center of the mirror and onto the wall. (C) c = the distance between the floor and mirror (or the thickness of the book) 4. You will goes to various distances away from the mirror, while making sure that the flashlight or laser pointer is held at the same height throughout the activity. At each location, you will measures the following distances, in centimeters.. x = the distance from the wall to the flashlight or laser pointer. . y = the height of the reflection on the wall 5. Collect at least 10 data points and enter them into the table below: Distance from flashlight to wall (r) Distance from reflection to floor (y) 6. On the cartesian plane or graphing paper, plot a graph of your data. 7. Plot the graph of the equation y = - a + c on the same grid as your data, you can use a graphing tool like x - b Geogebra or Desmos. Are your results consistent with results predicted by the graph? 8. Using the equation above, determine the distance from the floor of the reflection if you are:i. 3 meters from the wall ii. 4 meters from the wall Sample set - up: X