Help, I am in way over my head.

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
Ok people this is my last hope, I am doing my best to help my daughter study for finals, everything was going good until we reached the chapter on "Geometry Proofs". Ok, we past the point that I could offer help long ago..... Anyway this is the problem we are stuck with and need assistance badly.:confused:

Question:

Line AE intersets line DB, C is the point where they cross.
segment AE is congruent to segement DB
Given: segement AE is congruent to segement DB
segement CD is congruent to segement CE
Prove: segement AC is congruent to BC
(two-column proof)

Come on people I need assistance....................
 

ArJuN

Platinum Member
Aug 13, 2005
2,816
0
76
This is actually one of the easier proofs. It's been a while since I've done geometery proof, but does your daughter have a text book with the theorems written out?
 

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
we have looked all through the text book and yes they have them, however understanding how to get started is the bigger problem.Once we can figure out how to start then continueing will be easier.
 

RbSX

Diamond Member
Jan 18, 2002
8,351
1
76
You need a diaaaaaaaagram dude, then I could help you. This is from grade 11 though, sheesssssssh.

Linear Algebra and Calculus ftw.
 

RbSX

Diamond Member
Jan 18, 2002
8,351
1
76
Originally posted by: Grunt03
we have looked all through the text book and yes they have them, however understanding how to get started is the bigger problem.Once we can figure out how to start then continueing will be easier.

There are a series of rules or 'laws' saying something like..

Any line perpindicular to line AB = C or something like that, look up those rules and you will be able to do it.
 

acemcmac

Lifer
Mar 31, 2003
13,712
1
0
Originally posted by: RyanSengara
You need a diaaaaaaaagram dude, then I could help you. This is from grade 11 though, sheesssssssh.

Linear Algebra and Calculus ftw.

10th for me
 

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
ok my daughter is a freshman doing this stuff and as I said it is way above what I can assist her with.
 

RbSX

Diamond Member
Jan 18, 2002
8,351
1
76
Originally posted by: Grunt03
ok my daughter is a freshman doing this stuff and as I said it is way above what I can assist her with.


Actually you can assist her pefectly, there is NO math involved.

Just laws, it's a practice of logic and application of the rules.

 

JLGatsby

Banned
Sep 6, 2005
4,525
0
0
BWHAHAHAHAAHAHAHA

Geometry proofs were so easy they were actually fun. I remember that from 9th grade Honors Geometry.
 

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
currently we are stuck on reflexive property of congruent, then we have the given then defination of congruent segements. This is where we become lost, well not we, her I was lost a very long time ago.........
 

yosuke188

Platinum Member
Apr 19, 2005
2,726
2
0
I think you start by stating that line AE = segment AC + segment CE, and same for the line DB. (Line addition property so something like that)

Since AE = DB, AC + CE = DC + CB using the transitive property.

Since CD = CE, you can say AC = DC. (I'm gona guess that is subtraction property or something else)

Hope that helps
 

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
Are the segmets part of a triangle?
If it is than it has sumthin to do with CPCTC

no this is two line that intersect, are they equal and if so what is the reason?
 

myusername

Diamond Member
Jun 8, 2003
5,046
0
0
you just need a bunch of dots ..

:.
:.
:.
:.

Like so

Do that for like 9 lines and it's done! Guaranteed A+
 

blackdogdeek

Lifer
Mar 14, 2003
14,453
10
81
from what i remember the two colums are going to be:

1. your claim
2. the reason

so it would look something like:

column1.........................column2
AE = BD.........................given
AE - CD = BD - CD..........commutative property of something something
AE - CE = BD - CD...........some sort of substitution or something
AE = AC + CE.................some sort of addition of parts or something
BD = BC + CD................same as above
(AC + CE) - CE = (BC + CD) - CD........substituting into the above equation
AC + CE - CE = BC + CD - CD............some transitive something
AC + (CE - CE) = BC + (CD - CD).......some sort of commutative something
AC + 0 = BC + 0................something
AC = BC...........................something

sorry i don't know the names of the properties or laws that go in the second column.
 

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
RyanSengara
She clearly has no future in math if she can't understand basic geometric proofs.

I am sorry you are mistaken, she is in the 9th grade, speaks English, Japanese, Spanish and Sign language. She plays all three Sax's and the piano. On second thought your right she might as well call it quits.........
 

suse920

Diamond Member
Feb 7, 2005
6,889
0
0
Originally posted by: Grunt03
RyanSengara
She clearly has no future in math if she can't understand basic geometric proofs.

I am sorry you are mistaken, she is in the 9th grade, speaks English, Japanese, Spanish and Sign language. She plays all three Sax's and the piano. On second thought your right she might as well call it quits.........
keep on trying :) With proofs it will just sort of click after a lot of practice.
 

Grunt03

Diamond Member
Jun 24, 2000
3,131
0
0
to everyone, thanks for the help, I think now we have figured it out, or at least I hope so.