Geometry Reasoning in Algebra Section 2-4 Review: Naming Angles: 1. Use the diagram at the right to find the measure of each angle. a) Name an angle that is a vertical angle to b) Name the two angles whose sum is c) Name an angle adjacent and congruent to d) is a supplement of what angle(s)? e) is a complement to what angle? Section 2-4____________________________________________________________ Part I: Properties of Equality – Properties accepted as true in Algebra. Addition Property: Example: If then ______________________________ Subtraction Property: Example: If then _____________________________ Multiplication Property: Example :If then ______________________________ Division Property: then ______________________________ Example: If Reflexive Property: Example: x = ____ Symmetric Property: Example: If Transitive Property: Example: if , then . and , then . Substitution Property: Example: If x=52, then you can replace _____ with the value _____ in any expression. Distributive Property: Example: Part II: Properties of Congruence – True for measurable geometric Figures (segments, angles) Reflexive Property: Example: Symmetric Property: Example: If Transitive Property: Example: If or , then __________≅_______________ and , then ___________≅____________ Name the properties that justify each statement: 1. 3. If , then and _____________ , then Algebra Proofs: Give a reason for each step. 2. If then ___________________________ ______ Geometry Reasoning in Algebra Section 2-4 1. Solve for x: 2. Solve for x: 1) 1. ______________ 1) 1) _________ 2) 2. ______________ 2) 2) _______________ 3) 3. ________________ 3) 3) _______________ 4) 4) _______________ 3. Solve for x: 4. Solve for y: 1 1)________________ 1) 1) ___________ 2) 2)______________ 2) 2)_______________ 3) 3)______________ 3) 3)_____________ 4) 4)______________ 4) 4)_______________ 5 5)______________ 5) 5)________________ Geometry Proofs: Give a reason for each step 5. Given 6. Given: Find AB. Find x. 1) AC=21 1) _______________ 1) 2) AB+BC=AC 2)______________ 2) 3) 3)___________ 1)_____________ 2)____ 3) 3) __________ 4) 4)________________ 4) 4)___________ 5) 5)________________ 5) 5)___________ 6) y = 6 6)________________ 6) 6)___________ 7) AB=12 7)________________ Geometry 7. Find Reasoning in Algebra Section 2-4 . 8. Given: bisects Find x. 1) 1)______________ 1) bisects 1)________ 2) 2) substitution_____ 2) 2)________ 3) 3)_______________ 3) 3)__________ 4) _____=________ 4)______________ 4) 40=2x 4)_________ 5) x = _________ 5)_______________ 5) x=20 5)__________ 6) 6)________________ CHALLENGE: Given: KL = 3PM. Find x and show steps.