1. Geometry 2.2 Properties of Equality: POE’s & Properties of Congruence: POC’s

2. Addition POE If a = b and c = d, then a + c = b + d ½ = 0.5 and 2 = 2.0, thus ½ + 2 = 0.5 + 2.0

3. Subtraction POE If a = b and c = d, then a - c = b - d 10 = 10.0 and ¼ = 0.25, thus 10 – 1/4 = 10.0 – 0.25

4. Multiplication POE If a = b, then ca = cb ¾ = 0.75, thus 100(¾) = 100(0.75)

5. Division POE If a = b and c 0, then a/c = b/c 8 = 8.0 and 2 0, thus 8/2 = 8.0/2

6. Substitution POE If a = b, then either a or b may be substituted for the other in an equation or inequality. If x = 5, then (x) + 10 = (5) + 10

7. Distributive POE a(b + c) = ab + ac 5(x + 3) = 5x + 15

8. Reflexive Reflexive POE a = a Reflexive POC and and

9. Symmetric Symmetric POE If a = b, then b = a Symmetric POC If, then

10. Transitive Property Transitive POE If a = b, and b = c, then a = c Transitive POC If, and then

11. A Few Together Please turn to page 40. Let’s try #1-10. 1)Reflexive POE 2)Transitive POE 3)Symmetric POE 4)Subtraction POE 5)Division POE 6)Multiplication POE 7)Distributive POE 8)Addition POE 9)Substition POE 10)Transitive POE

12. 5) Justify each step(from the HW) 1) 2/3B = 8 – 2B 2) 2B = 3(8 – 2B) 3) 2B = 24 – 6B 4) 8B = 24 5) B = 3 1) Given 2) Mult. POE 3) Distr. POE 4) Add. POE 5) Div. POE

13. CE 12) Complete the Proof Given ST = RN; IT = RU Prove: SI = UN 1) ST = RN 2) ST = SI + IT RN = RU + UN RN = RU + UN 3) SI + IT = RU + UN 4) IT = RU 5) SI = UN 1) Given 2) Segment Add. Post. 3) Subst. POE 4) Given 5) Subtr. POE.S.S.I.I.T.T.R.R.U.U.N.N

14. Homework 2.2 CE #12 WE #1-11