Lesson 3

Using a Coordinate Map

Est. Class Sessions: 2–3

Daily Practice and Problems

Teacher Notes
X

TIMS Task


    1. Answers will vary. Possible response: I know it is greater than 90° because 90° is a square corner and my angle is larger than a square corner.

    2. Answers will vary. Possible response: I know my angle is less than 45°because 45° is half the size of a square corner. This angle is smaller than half of a square corner.
  2. 100°; The sum of all three angles is 180°. 40 + 40 + 100 = 180.
  3. No; 70° + 70° + 50° = 190°. The sum of the angles of a triangle is 180°.
  4. 63°; First I added 90° + 27° = 117°. Then I subtracted 180° − 117° = 63°.
  5. 84°; 32° + 64° = 96°. 180° − 96° = 84°.

H. Angles and Triangles

    1. Draw an angle that is greater than 90°. Label the angle YTV. Explain how you know it is larger than 90°.
    2. Draw an angle that is less than 45°. Label the angle RGM. Show or tell how you know the angle is less than 45°.
  2. Triangle ADK has two angles that are 40°. What is the measure of the third angle? Show how you decided.
  3. Can a triangle have two 70° angles and one that measures 50°? How do you know?
  4. One angle in Triangle QFP is a right angle. A second angle is 27°. What is the measure of the third angle? Show or tell how you decided.
  5. One angle in a triangle measures 32°. Another angle is twice as large. What is the measure of the third angle? How do you know?