1. 4.4 Proving Δs are  : SSS and SAS
Geometry

2. Remember
As of yesterday, Δs could only be  if ALL sides AND angles were 
NOT ANY MORE!!!!
There are two short cuts to add.

3. Post. 4-4-1 Side-Side-Side (SSS)  post
If 3 sides of one Δ are  to 3 sides of another Δ, then the Δs are .

4. A
Meaning:
___
___ If
, then ΔABC  ΔEDF. B C
___ E
___
___ D
___ F

5. Ex. 1 Given: Prove: ΔQRS  ΔUTS10 10 R S T

6. Proof Statements Reasons 1.)____________ 1.) ___________
1.)____________ ) ___________
)___________ ) ____________
3.)____________ 3.)_____________
4.)____________ 4.)_____________

7. Post. 4-4-2 Side-Angle-Side post. (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 .

8. , and C  X, then ΔABC  ΔZYX.If
, and C  X, then ΔABC  ΔZYX. B Y ) ( C A X Z

9. Ex. 2 Given: , Prove: Δ VXW  Δ ZXY1 2 Y V

10. Proof Statements Reasons 1.)____________ 1. ___________
1.)____________ ___________
)___________ ____________
3.)____________ 3. _____________

11. Ex. 3 Given: Prove: Δ QRT  Δ SRT.

12. Proof Statements Reasons 1.)____________ 1. ___________
1.)____________ ___________
)___________ ____________
3.)____________ 3. _____________

13. Ex. 4 Given: Prove: Δ DRA  Δ DRG.

14. Proof Statements Reasons 1.)____________ 1.) ___________
1.)____________ ) ___________
)___________ ) ____________
3.)____________ 3.)_____________
4.)____________ 4.)_____________
5.)____________ 5.)_____________

15. Show that the triangles are congruent for the given value of the variable.
ΔGHJ  ΔIHJ, x = 4
(GJ = 5, IJ = 2x – 3) H
3x-9 3 G I
#5 on pg. 245 J

16. Proof Statements Reasons 1.)____________ 1.) ___________
1.)____________ ) ___________
)___________ ) ____________
3.)____________ 3.)_____________
4.)____________ 4.)_____________
5.)____________ 5.)_____________

17. Assignment