Pythagorean theorem proof using similarity | Geometry | Khan Academy

Proof of the Pythagorean Theorem using similarity

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[brindaparthasarathy]

Your lecture on Pythagorean Theorem is pristine.Thanks a million.

[Androconus]

Brilliant! I can't pause or re-wind my teacher, but I can to you! Thank you! liked, Favorited and subscribed until further notice.

[darkreaper]

I wish I had these lectures when I was in school. My maths scores would be completely different.

[babykikino]

I had learned Pythagorean Theorem last year in middle school but no one teach me why a^2+b^2=c^2
yr teaching is easy to understand
thx a lot~!

[NayimKay]

I love learning from you, fellow Khan here.

[Slothd]

And it seems in many schools, teachers suffice themselves with teaching you how to solve a problem without telling you why that works. And I personally believe retention is better attaned when one nows why something works just as much as when they learn how to do the something.

[LOLworldofwarcrafLOL]

We're learning about geometry in class now, and we are at a sub-chapter about just this. I didn't understand it in class, but now i did! Thanks :D

[lochlainnmcgall]

Day before my math exam, didn't learn this thank you some much. Some hero just don't wear capes.

[rolandsmith]

great video, even clearer if you were to draw the 3 triangles

[theckiemnstr]

Sal, when you were young did you figure this out for yourself? Because I was never able to figure this out, you just showed me. Thanks

[jeremiah-iibt]

Does anyone know why he split the triangle into three ? I understand the gist but don’t understand why he used cos aswell

[ahadmoeen]

We have to prove that except that we also have to prove the triangles similar.

[whengale]

how did you know to add a² = cd and b² = ce? adding those two equations seems totally arbitrary to me and i don't understand why.

[jennytan]

why did you add a^2 = cd and b^2 = ce together?

[JoshiNischal]

Can i know which software do you use to make these videos?

[TheShubLub]

At 8:50 mind=blown.... How come I didn't learn this in school? I mean we used pythagorean theorem, but we had no idea what it really was.

[ManualShark]

Because the 2 smaller similar triangles make up the big triangle

[ale]

what is this sftwre you are using called?

[wolfieswifty]

i always mistaken the hypotenuse with hypothalamus :(

[jolo]

Can you do a video about venn perplexor?
My daughter is the gifted 5th grade class and is having a tiny problem with it.