1. Using geometric notation
Slideshow 42, Mathematics
Mr Richard Sasaki, Room 307

2. Objectives Understand some extra notation for shape construction
Use such notation for explanation of shape properties

3. Chapter 5
Chapter 5 is mostly about proof. For this reason, we will be proving certain properties in triangles and parallelograms.
We will need some new notation for this.

4. PHRASES F
Line AB is _________ to line CD and _______________ to line FE.
parallel C D
perpendicular A B E
Lines of non-infinite lengths we call ______________.
line segments

5. Notation - Review ∠𝐴𝐵𝐶=∠𝑋𝑌𝑍 𝐴𝐵=𝑋𝑌 ∆𝐴𝐵𝐶≅∆𝑋𝑌𝑍 ∆𝐴𝐵𝐶~∆𝑋𝑌𝑍
Angle ABC is equal to angle XYZ.
𝐴𝐵=𝑋𝑌
Distance AB is the same as distance XY.
∆𝐴𝐵𝐶≅∆𝑋𝑌𝑍
Triangle ABC is congruent to triangle XYZ.
∆𝐴𝐵𝐶~∆𝑋𝑌𝑍
Triangle ABC is similar to triangle XYZ.

6. Notation 𝐴𝐵 ∥ 𝑋𝑌 𝐴𝐵 ⊥ 𝑋𝑌 𝐴𝐵 = 𝑋𝑌 𝐴𝐵
Line segment AB is parallel to line segment XY.
𝐴𝐵 ∥ 𝑋𝑌
Line segment AB is perpendicular to line segment XY.
𝐴𝐵 ⊥ 𝑋𝑌
Line segment AB is the same length as line segment XY.
𝐴𝐵 = 𝑋𝑌
A line of infinite length passes through A and B. 𝐴𝐵

7. Answers 𝐴𝐵 , 𝑋𝑌 , 𝐴𝐵 ∥ 𝑋𝑌 , 𝐴𝐵 ⊥ 𝑋𝑌 𝐴𝐵 intersects 𝑋𝑌
𝐴𝐵 , 𝑋𝑌 , 𝐴𝐵 ∥ 𝑋𝑌 , 𝐴𝐵 ⊥ 𝑋𝑌
𝐴𝐵 intersects 𝑋𝑌
Parallel lines never touch so they can’t intersect. Therefore they can’t be perpendicular. S E T D U G R F A D C B

8. Line types Line passing through A and B Line segment from A to B
Ray from A, passing through B B