Geometry Advice from former students: “Do your homework. If you don’t you won’t know what you need help on.” Today: Homework Questions 1.2 Instruction Practice
1.2 Homework Quiz Take out a blank piece of notebook paper. Label the top with your name and Chapter 1 Homework Quiz. Write down today’s date, 8/31, p. 20 #46. Write out the question, including picture, your work and your final answer.
EXAMPLE Use the figure to name a line containing the point X. A. line X B. line c C. line Z D.
EXAMPLE B. A. B. C. D.
5-Minute Check 3 Over Lesson 1–1 Name a line on plane Z. A. AT B. AW C. AQ D. BQ 5-Minute Check 3
EXAMPLE A. 2 mm B. 1.8 mm C. 18 mm D. 20 mm
EXAMPLE Name three points that are collinear. A. B, O, and X B. X, O, and N C. R, O, and B D. A, X, and Z
EXAMPLE A. point X B. point N C. point R D. point A
5-Minute Check 2 Over Lesson 1–1 What is another name for AB? A. AA B. AT C. BQ D. QB 5-Minute Check 2
Over Lesson 1–1 Which of the following statements is always false? A. The intersection of a line and a plane is a point. B. There is only one plane perpendicular to a given plane. C. Collinear points are also coplanar. D. A plane contains an infinite number of points.
1.2 Linear Measure Content Standards G.CO.1 Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc. G.CO.12 Make formal geometric constructions with a variety of tools and methods (compass and straightedge, string, reflective devices, paper folding, dynamic geometric software, etc.). Mathematical Practices 6 Attend to precision.
1.2 Linear Measure You identified and modeled points, lines, and planes. Measure segments. Calculate with measures.
1.2 Linear Measure Objectives: Sketch relationships in Geometry. Use the segment addition postulate Know the differences between congruence and equality Vocabulary: line segment, ray, distance, betweenness, congruent
1.2 Linear Measure Vocabulary A is 5 units from the origin. Distance: how far apart two points are. Also known as length. NOTE: length or distance is always positive. A • 4 -5 B • A is 5 units from the origin. B is 4 units from the origin AB = 9 units
1.2 Linear Measure A B C 5.4 cm 3.2 cm What is the length of ? How do you know? Reason: Segment Addition Postulate AB + BC = AC 5.4 + 3.2 = 8.6
1.2 Linear Measure Q R S 12 in 6 in Find RS. No line means measure. By SEGMENT ADDITION POSTULATE (SAP) … QR + RS = QS Plug in and solve. QR = 6 in Put back in picture.
1.2 Linear Measure Q R S Vocabulary 12 in 6 in 6 in Since QR = 6in and RS = 6in, QR = RS. No line means measure, use equals sign. Vocabulary Two segments with equal measure are congruent. Notation:
congruent: items that are the same size and shape. Use the symbol . = means same size means same shape means same shape and size ~ ~ =
Assignment Advise from former students: “Do your homework. If you don’t you won’t know what you need help on.” Section 1.1-1.2 Review p 78 #1-10 Get supplies