Review the triangle congruence criteria and use them to determine congruent triangles.

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FrancescaG

8 years agoPosted 8 years ago. Direct link to FrancescaG's post “In the "check your unders...”

In the "check your understanding," I got the problem wrong where it asked whether two triangles were congruent. Both triangles listed only the angles and the angles were not the same. I put no, checked it, but it said it was wrong. I thought that AAA triangles could never prove congruency. Please help!

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(42 votes)

Kadan Lam

8 years agoPosted 8 years ago. Direct link to Kadan Lam's post “There are 3 angles to a t...”

There are 3 angles to a triangle. The question only showed two of them, right? You could calculate the remaining one. For example, a 30-60-x triangle would be congruent to a y-60-90 triangle, because you could work out the value of x and y by knowing that all angles in a triangle add up to 180. Then, you would have 3 angles.

(33 votes)

Sierra Kent

8 years agoPosted 8 years ago. Direct link to Sierra Kent's post “if there are no sides and...”

if there are no sides and just angles on the triangle, does that mean there is not enough information?

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(23 votes)

POWA

8 years agoPosted 8 years ago. Direct link to POWA's post “A triangle will *always* ...”

A triangle will

**always**have a sum of 180° (3 angles a+b+c=180°). So a huge triangle will have the same sum of angles as a tiny one, but the area will be different.I hope this was a little helpful!

BooneJalyn

5 years agoPosted 5 years ago. Direct link to BooneJalyn's post “how is are we going to us...”

how is are we going to use when we are adults ?

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(24 votes)

Rosa Skrobola

2 years agoPosted 2 years ago. Direct link to Rosa Skrobola's post “If you were to come at th...”

If you were to come at this from the perspective of the purpose of learning and school is primarily to prepare you for getting a good job later in life, then I would say that maybe you will never need Geometry. Assuming of course you got a job where geometry is not useful (like being a chef). Now, if we were to only think about what we learn, when we are young and as we grow older, as to how much money it’s going to make us, what sort of fulfillment is that? You could argue that having money to do what you want is very fulfilling, and I would say yes but to a point.

The reason why people find such enjoyment in watching the olympics is not because we just like to see people win money and awards (though that is an element) but because it is amazing and inspiring to see people who have put in the effort and discipline to become as skilled as they are (which is also why people love the movie Rocky) Humans are inspired by effort. I would also argue that humans are fulfilled by effort and discipline. When people exercise or learn the piano, usually there is this annoyance or a desire to just sit on the couch, but once those things are done we feel this sense of accomplishment, maybe even happiness. Things that require effort whether it be mental or physical makes people feel fulfilled because doing those things push your boundaries, and when we push what we thought was our limit of intelligence or skill we realize that our boundaries are much farther than we imagined.

I am not saying learning to make money is bad, but I think you need a balance between learning to make money and learning to understand the world, yourself, or to improve yourself.(25 votes)

ethanrb.mccomb

8 years agoPosted 8 years ago. Direct link to ethanrb.mccomb's post “Is there any practice on ...”

Is there any practice on this site for two columned proofs?

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(24 votes)

elidnewlin

a year agoPosted a year ago. Direct link to elidnewlin's post “They tell me this AFTER I...”

They tell me this AFTER I had to figure it for the quiz?

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(17 votes)

denzel.chukwu

a year agoPosted a year ago. Direct link to denzel.chukwu's post “It's just restating infor...”

It's just restating information from the videos, so you didn't need it.

(6 votes)

Breannamiller1

8 years agoPosted 8 years ago. Direct link to Breannamiller1's post “I'm still a bit confused ...”

I'm still a bit confused on how this hole triangle congruent thing works. I think I understand... but i'm not positive. Could someone please explain it to me in a simpler way? Thank you very much.

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(8 votes)

Timothy Grazier

8 years agoPosted 8 years ago. Direct link to Timothy Grazier's post “Ok so we'll start with SS...”

Ok so we'll start with SSS(side side side congruency). If all the sides are the same, they would need to form the same angles, or else one length would be different. For SAS(Side Angle Side), you would have two sides with an angle in between that are congruent. If you have an angle of say 60 degrees formed, then the 3rd side must connect the two, or else it wouldn't be a triangle. So, the third would be the same as well as on the first triangle. For ASA(Angle Side Angle), say you had an isosceles triangle with base angles that are 58 degrees and then had the base side given as congruent as well. Whatever the other two sides are, they must form the angles given and connect, or else it wouldn't be a triangle. Hope this helps

(13 votes)

Brendan

7 years agoPosted 7 years ago. Direct link to Brendan's post “If a triangle is flipped ...”

If a triangle is flipped around like looking in a mirror are they still congruent if they have the same lengths

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(8 votes)

Bradley Reynolds

7 years agoPosted 7 years ago. Direct link to Bradley Reynolds's post “If the side lengths are t...”

If the side lengths are the same the triangles will always be congruent, no matter what.

(10 votes)

aidan mills

5 years agoPosted 5 years ago. Direct link to aidan mills's post “if all angles are the sam...”

if all angles are the same it is right i feel like this was what i was taught but it just said i was wrong

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(8 votes)

Markarino /TEE/DGPE-PI1 #Evaluate

5 years agoPosted 5 years ago. Direct link to Markarino /TEE/DGPE-PI1 #Evaluate's post “I'm really sorry nobody a...”

I'm really sorry nobody answered this sooner. It's a good question.

That happens to me. I remember something so clearly, and then I find out it never happened. I was really shocked when I was doing an exercise and they said that -x squared was a negative number. I was sure it was supposed to be positive, and I was in the middle of reporting a mistake. But then I looked it up and found out I was wrong.

But I understand what they are saying about triangles. Imagine if you had a triangle, lets say the angles were 30, 60, and 90. If I have one where the short side is 20 inches, I can scale it up, make another 30, 60, 90 triangle, maybe the short side is 25 inches, and it has all the same angles, but it is bigger. That's why you have to know at least one of the sides if you know all of the angles. I hope that helps :-) Good luck!

(6 votes)

ryder tobacco

6 years agoPosted 6 years ago. Direct link to ryder tobacco's post “when am i ever going to u...”

when am i ever going to use this information in the real world?

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(6 votes)

mayrmilan

6 years agoPosted 6 years ago. Direct link to mayrmilan's post “These concepts are very i...”

These concepts are very important in design. For example, when designing a roof, the spoiler of a car, or when conducting quality control for triangular products. It is

**much**faster to compare known angles or sides than it is to measure every single side. Sometimes, it is not possible. For example, when building a roof, you want to make sure it matches the design. If you don't want to climb the whole thing after it is built and use a giant measuring tape, you can simple measure one side and two angles.(7 votes)

RN

4 years agoPosted 4 years ago. Direct link to RN's post “Could anyone elaborate on...”

Could anyone elaborate on the Hypotenuse postulate? Is it a valid postulate for

**all**right triangles?•

(4 votes)

Iron Programming

4 years agoPosted 4 years ago. Direct link to Iron Programming's post “The *HL Postulate* says t...”

The

**HL Postulate**says that if you have two right triangles with the hypotenuse and 1 leg of equal lengths then the triangles are congruent. This is true for all right triangles.Also, if you think about this it is very similar to the SSS postulate since due to the Pythagorean theorem (a^2 + b^2 = c^2) if we ever know 2 sides of a right triangle, we always know the 3rd.

Hope this helps! :-)

- Convenient Colleague(9 votes)