1 / 11

2.4 Reasoning in Algebra

2.4 Reasoning in Algebra. Chapter 2. Properties of Equality (pg 89 in text). Addition Property If a = b , then a + c = b + c Subtraction Property If a = b , then a – c = b – c Multiplication Property If a = b , then a · c = b · c

kaden
Download Presentation

2.4 Reasoning in Algebra

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 2.4 Reasoning in Algebra Chapter 2

  2. Properties of Equality (pg 89 in text) • Addition Property If a = b, then a + c = b + c • Subtraction Property If a = b, then a – c = b – c • Multiplication Property If a = b, then a·c = b ·c • Division Property If a = b and c = 0, then a = b c c • Reflexive Property a = a • Symmetric Property If a = b, then b = a • Transitive Property If a = b and b = c, then a = c • Substitution Property If a = b, then b can replace a in any expression

  3. The Distributive Property *You also assume that other properties from Algebra are true. • Distributive Property a(b + c) = ab + ac

  4. Justifying Steps in an Equation Solve for x and justify each step. B Given: m< AOC = 139 A O C m< AOB + m< BOC = m< AOC

  5. Fill in each missing Reason: Given: LM bisects <KLN LM bisects <KLN a. m<MLN = m<KLM b. 4x = 2x + 40 c. 2x = 40 d. x = 20 e. M K (2x + 40) 4x N L

  6. Solve for y and Justify each step. Given: AC = 21 2y 3y - 9 B C A

  7. Properties of Congruence • Reflexive Property AB = AB <A = <A • Symmetric Property If AB = CD, then CD = AB • Transitive Property If AB = CD and CD = EF, then AB = EF If <A = <B and <B = <C, then <A = <C

  8. Using Properties of Equality and Congruence Name the property of equality or congruence that justifies each statement. • <K = <K • If 2x – 8 = 10, then 2x = 18 • If RS = TW and TW = PQ, then RS = PQ. • If m<A = m<B, then m<B = m<A

  9. Fill in the reason that justifies each step: E Solve for x: m<CDE + m<EDF = 180 x + (3x + 20) = 180 4x + 20 = 180 4x = 160 x = 40 x (3x + 20) C D F a. b. c. d. e.

  10. Fill in the reason that justifies each step: Solve for n. Given: XY = 42 XZ + ZY = XY 3(n + 4) + 3n = 42 3n + 12 + 3n = 42 6n + 12 = 42 6n = 30 n = 5 3(n + 4) 3n X Z Y a. b. c. d. e. f.

  11. Homework • Pg 91 1-24, 27-31

More Related