Proof: Triangle altitudes are concurrent (orthocenter) | Geometry | Khan Academy

Showing that any triangle can be the medial triangle for some larger triangle. Using this to show that the altitudes of a triangle are concurrent (at the orthocenter).

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[ashwinarora]

all the videos of khanacademy are a life saver

[bruceedward]

Beautiful, simple and elegant proof, thank you

[muhammadjavid]

I would like to request the tutor to make a video on how to find and prove the orientation of vectors!

[xedgesharpz]

Ok, now my question is why all the perpendicular bisectors are

[tapaspal]

How is centroid of a triangle is equal to the orthocentre of medial triangle

[hedonism]

The new art history videos - will they be being embedded on the KA website soon?

[Nitrodino]

i dont see how people dont WATCH THESE

[rajeshkumar-ecvj]

Pls could u give the proof for concurrency of meadian s of triangle without using vectors

[muhammadjavid]

If two vectors A and B are non zero vectors and A=√2B then what is the orientation of these vectors means parallel, anti parallel, coplanar and concurrent? Can anybody explain?

[spiderjump]

is there another way to prove that orthocenter is concurrent?