Help needed on problem

Davey Jones

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Apr 29, 2021
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Well, your two triangles already have two pairs of congruent sides (AC and SE as stated, and the shared side CS). You have a couple of theorems for triangle similarity involving two sides: SSS, and SAS. So, you need to either show sides AS and CE are congruent (giving SSS), or the included angles are congruent between the sides we already know about (so angles ACS and ESC, thus giving SAS).

So, which would be easier to show congruent: the third sides, or the included angles?

hint: I haven’t yet taken advantage of the fact that AC and SE are parallel, or the fact that CS is a transversal to the parallel segments.
 

skeeter

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Dec 15, 2005
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looks like you can use SAS to prove the two triangles are congruent
 

pka

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Hannah1234

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Well, your two triangles already have two pairs of congruent sides (AC and SE as stated, and the shared side CS). You have a couple of theorems for triangle similarity involving two sides: SSS, and SAS. So, you need to either show sides AS and CE are congruent (giving SSS), or the included angles are congruent between the sides we already know about (so angles ACS and ESC, thus giving SAS).

So, which would be easier to show congruent: the third sides, or the included angles?

hint: I haven’t yet taken advantage of the fact that AC and SE are parallel, or the fact that CS is a transversal to the parallel segments.
Any way you can break it down a little more
 

Subhotosh Khan

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Any way you can break it down a little more
Well, your two triangles already have two pairs of congruent sides (AC and SE as stated, and the shared side CS). You have a couple of theorems for triangle similarity involving two sides: SSS, and SAS. So, you need to either show sides AS and CE are congruent (giving SSS), or the included angles are congruent between the sides we already know about (so angles ACS and ESC, thus giving SAS).

So, which would be easier to show congruent: the third sides, or the included angles?

hint: I haven’t yet taken advantage of the fact that AC and SE are parallel, or the fact that CS is a transversal to the parallel segments.
Exactly where are you getting lost?

You have a couple of theorems for triangle similarity involving two sides: SSS, and SAS

If you don't know those theorems of triangle congruency (Side-side-side and Angle-side-angle) look up in your text-book or use Google.

Can you post your work/understanding prior to get lost?
 

Hannah1234

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Apr 28, 2021
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Over all I’m getting lost I don’t get this at all
 

lev888

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Jan 16, 2018
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Over all I’m getting lost I don’t get this at all
We can't help you if you don't contribute to the process. If you have been asked to prove that 2 triangles are congruent you must have been studying some methods of doing it. What are they?
 

lex

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Mar 3, 2021
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1620246113942.png
Top and bottom lines are parallel, so the marked angles are equal ('alternate angles are equal').
The coloured lines are known to be equal (red/red and green/green).
So each triangle has a green side, red side and a yellow angle in-between.
Showing this is sufficient to say that the two triangles are congruent.
That is what we mean by "SAS" - it is a theorem that when two sides and the angle in-between are the same in both triangles, then the two triangles are known to be congruent.
 
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