Practice A Building Blocks of Geometry Name each geometric figure. 1. 2. 3. 4. 5. 6. Use the diagram to choose the correct answer. 7. Which of the following does not name a line on the diagram? A Line YQ B Line WZ C ZX D QW 8. Which two points cannot be used to name a ray on the diagram? F Q and Y G Z and X H X and Y J W and Q 9. How many points are needed to define a line or line segment? 10. Lynn named this ray PQ. Explain her error and give the correct name for the ray.
Practice B Building Blocks of Geometry Use the diagram to name each geometric figure. 1. two points 2. a plane 3. a line segment 4. a point shared by two lines 5. a line Use the diagram to give a possible name to each figure. 6. two different ways to name the line 7. four different names for rays 8. another name for QP 9. Is the following statement always true, sometimes true, or never true? Explain your reasoning. A line is longer than a line segment. 10. Using endpoints as your basis, explain how a line, a line segment, and a ray are different.
Practice C Building Blocks of Geometry Use the diagram to name each geometric figure. 1. a point shared by three lines 2. three points on the same line 3. four different rays 4. four different names for the same line segment Draw and label an example of each geometric figure. 5. PQ 6. ST 7. XY 8. plane FGH 9. If 3 points are labeled on a line, how many different line segments can be named on that line? How many different rays? 10. Name every geometric figure that is part of line AB.
Review for Mastery Building Blocks of Geometry Here are terms that can help you understand geometry. A point is an exact location. A point has no size. Use a capital letter to name a point. A line is a straight path that extends without end in opposite directions. A line has infinite length, but no width. Two points name a line. A plane is a flat surface that extends without end in all directions. A plane has infinite length and width, but no depth. A plane is named by 3 points on the plane that are not on a line. A line segment has two endpoints. The length of a line segment can be measured. A line segment is named by its endpoints. A ray has one endpoint and extends without end in one direction. A ray is named by its endpoint first and another point on the ray. Use the diagram to name each geometric figure. 1. two points 2. two lines 3. a plane 4. two line segments 5. two rays 6. a point shared by two lines
Challenge Points of Light Astronomers have divided the sky into 88 constellations, or groups of stars. To map these constellations, astronomers use a point for each star and draw imaginary lines between the points. One of the easiest groups of stars to see is called the Big Dipper. The Big Dipper is not officially a constellation. It is only part of a large constellation called Ursa Major, or Great Bear. Imagine the stars of Ursa Major are labeled as shown below. Follow these instructions to make a star map of Ursa Major. 1. Use line segments to connect points A G in alphabetical order, and then draw DG. 2. Use line segments to connect points G L in alphabetical order, and then draw FJ. 3. Use line segments to connect points M O in alphabetical order. Then draw EM and MP. 4. Label the star grouping formed by the 7 points A G as the Big Dipper. 5. Then label each point of the Big Dipper with its proper star name: A: Alkaid; B: Mizar; C: Alioth; D: Megrez; E: Phecda; F: Merak; G: Dubhe
Problem Solving Building Blocks of Geometry Place your hand down flat on a sheet of paper. Draw a point at the tip of your thumb, the tip of your middle finger, and the tip of your pinky. 1. Label the thumb point A, the middle finger point B, and the pinky point C. 2. Name all the planes you possibly can with points A, B, and C. 3. Draw and name all the lines you can make with points A, B, and C. 5. Name all the rays possible using points A, B, and C. 4. Name all the line segments possible using points A, B, and C. 6. Choose one line that you drew. Give all the different possible names for that line. Circle the letter of the correct answer. 7. Which of the following has exactly one endpoint? A OP B AB C TR D SM 8. Which of the following is a straight path that extends without end in opposite directions? F a point G a line H a ray J a line segment 9. Which statement is false? A An infinite number of lines can be drawn through one point. B Exactly one line can be drawn between two points. C A line contains exactly one ray. D If points A and B are on a line, then line segment AB and line segment BA are the same. 10. Why is the false statement in Exercise 9 not true? F Any point on a line defines another ray on the line. G A line contains exactly two rays. H A line contains exactly five rays. J A line does not contain any rays.
Reading Strategies Understanding Symbols A point marks an exact location in space. Read: point T. A capital letter is used to name a point. A line is a straight path that extends forever in both directions. Read: line DR or line RD. Two points on the line name a line. A ray is part of a line that has one endpoint and goes on forever in one direction. Read: ray SM. A line segment is part of a line between two endpoints. Use the two endpoints to name the line. Read: segment VW or segment WV. Use this figure to answer the questions. 1. What symbols would you use to name the line segment? 2. What symbols would you use to name the line? 3. What symbols would you use to name the ray? 4. Write the name of the point. 5. What is the difference between a line and a ray?
Puzzles, Twisters & Teasers Is it the Truth? Determine which statements are true. Rearrange the letters of the true statements to solve the riddle. 1. R Point G is onjg. 2. O DH can also be writtenhd. 3. B JKG is a plane. 4. S GK is a ray. 5. A A point is named by a capital letter. 6. N KD is a ray. 7. U A line segment has only one end point. 8. T FKG is a plane. 9. C A line is a straight path that extends without end in all directions. 10. O A ray is named by its endpoint first. What do you call a song played on an automobile radio? A
Answers CODE 60801 LESSON Practice A 1. point P, or P 2. AB or BA 3. FG 4. LM or ML 5. plane XYZ 6. JK or KJ 7. B 8. H 9. 2 points 10. A ray must be named by its endpoint first. The correct name is QP. Practice B Possible answers are given. 1. A and B 2. plane ABD 3. BD 4. A 5. CD Possible answers are given. 6. line XY and XY 7. ray PY, ray PX, PY, and PX 8. PQ 9. It is always true, because a line segment only extends between two endpoints, but a line extends without end in opposite directions. 10. A line has no endpoints, a ray has one endpoint, and a line segment has two endpoints. Practice C Possible answers are given. 1. C 2. A, C, and E 3. CD, CE, CF, and CG 4. AC, CA line segment AC, line segment CA 5. 6. 7. 8. 9. 3 different line segments and 6 different rays 10. points A and B, AB AB Review for Mastery, BA, BA, and 1. R, S 2. PQ and RQ 3. STU 4. PQ and QR 5. QP and QR 6. Q Challenge Problem Solving
1. Check students drawings. 2. plane ABC 3. AB, AC, and BC 4. AB, AC, and BC 5. AB, AC, BA, BC, CA, and CB 6. Possible answer: AB, BA, line AB, and line BA 7. D 8. G 9. C 10. F Reading Strategies 1. ST or TS 2. DQ or QD 3. MR 4. point Z 5. Possible answer: A line is a path that goes forever in both directions. A ray has one endpoint and goes forever in one direction. Puzzles, Twisters & Teasers 1. True 2. True 5. True 6. True 8. True 9. True 10. True C A R T O O N