Proving Δs are : SSS and SAS
Side-Side-Side (SSS) Postulate If 3 sides of one Δ are to 3 sides of another Δ, then the Δs are .
A Meaning: ___ ___ If seg AB seg ED, seg AC seg EF & seg BC seg DF, then ΔABC ΔEDF. B C ___ E ___ ___ D ___ F
Given: seg QR seg UT, RS TS, QS=10, US=10 Prove: ΔQRS ΔUTS
Proof Statements Reasons 1. 1. given 2. QS=US 2. subst. prop. = 3. Seg QS seg US 3. Def of segs. 4. Δ QRS Δ UTS 4. SSS post
Side-Angle-Side Postulate (SAS) If 2 sides and the included of one Δ are to 2 sides and the included of another Δ, then the 2 Δs are .
If seg BC seg YX, seg AC seg ZX, and C X, then ΔABC ΔZXY. ) ( C A X Z
Given: seg WX seg. XY, seg VX seg ZX, Prove: Δ VXW Δ ZXY 1 2 Y V
Proof Statements Reasons 1. seg WX seg. XY 1. given seg. VX seg ZX 2. 1 2 2. vert s thm 3. Δ VXW Δ ZXY 3. SAS post
Given: seg RS seg RQ and seg ST seg QT Prove: Δ QRT Δ SRT.
Proof Statements Reasons 1. Seg RS seg RQ 1. Given seg ST seg QT 2. Seg RT seg RT 2. Reflex prop 3. Δ QRT Δ SRT 3. SSS post
Given: seg DR seg AG and seg AR seg GR Prove: Δ DRA Δ DRG.
Proof Statements seg DR seg AG Seg AR seg GR 2. seg DR Seg DR 3.DRG & DRA are rt. s 4.DRG DRA 5. Δ DRG Δ DRA Reasons Given reflex. Prop of lines form 4 rt. s 4. Rt. s thm 5. SAS post.