Question

Which of the following is not a way to prove triangles congruent?
SSS
SAS
SSA
ASA

Answer 1

Am I stupid or are all these congruence theories?

Answer 2

lol. look at all the guests viewing.

Answer 3

These are not all triangle congruence theorems or postulates.

Answer 4

An imposter is in the mix.

Answer 5

ahh. so I am stupid.

Answer 6

:D that sucks.

Answer 7

I'm from the UK and when I did geometry we didn't have these acronyms
just 3 conditions for congruency of triangles
1. 2 sides and included angle
2. 3 sides
3. 2 angles and corresponding side

Answer 8

AHHHHH!! it's ASA!

Answer 9

right? If so, why?

Answer 10

ASA works

SSA doesn't

Answer 11

Check the attached chart.

Answer 12

oh, stupid me. I was confusing SSA with AAS.

Answer 13

ugg. Thanks, @PaxPolaris

Answer 14

Thanks for the chart @Directrix

Answer 15

i'm not sure why you need ASA and AAS

Answer 16

- that is covered by ' 2 angles and the corresponding side'.

Answer 17

* those are covered

Answer 18

yes, I know. these so called abbreviations are stupid.

Answer 19

nothing I can do though.

Answer 20

well they are easier to write...

Answer 21

but not easier to remember.

Answer 22

yes - i agree
I had never come across them until I joined openstudy

Answer 23

this is an example showing SSA doesn't work:\[\triangle PQR \cancel \cong \triangle PQS\]
S: QR = QS
S: PQ = PQ
A: P = P

Answer 24

right - that is what is called ' the ambiguous case'.

Answer 25

0, 1, or 2 triangles can be built with two sides and an non-included angle.