Part 1 of proof of Heron's formula | Perimeter, area, and volume | Geometry | Khan Academy

Part 1 of the proof of Heron's Formula

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[griftorifto]

I love how I could pretty much prove this on my own before I even watched this video. Yet a few moths ago a I barely passed my test by 1%
. Somehow khan academy has boosted me beyond ever actually needing to watch the videos. Like I find everything so easy in class now having it explained to me twice is useless. Thanks Khan, I love math!

[Monique_Johnson]

Well, as of today, I don't get Heron's proof of formula here and I know with time, eventually, I will comprehend. Khan Academy is wonderful and I'll be back to share my transformation on this particular proof.

[mashupstyles]

Thank you you simplified the last step! :D

[lashamamaladze]

It is so entertaining, I'm hooked ;) and of course informative and I loved it. If you don't mind telling me, what pad are you using to draw? It looks like it has no lag. cheers and thanks for the video, it is a good brain exercise too ;)

[TheMusicalTech]

Which software you use for making videos?

[MaryDeioma]

Please provide a link to the calculator application?

[kushshrivastava]

How to download the calculator you used ?👌

[ahmedbaig]

I am glad that height is discovered. When we will mutiply it with the base we will definitely get the area of the triangle. In case of 1' 2 and 3 first we may find the height of that particular triangle. In case we don' t got it then there the problem of discivoring height would be remain a mystery.

[simonshugar]

I know; the "triangle" has an area of 0.

[ahmedattaalla]

Phillip wow u made a careless mistake a triangle cannot have sides 1, 2, 3 based on triangle inequality that would just make a line

[redjr]

Youtube won't let me type the up arrow so just imagine that the ampersand: & represents the power symbol.

(c - x) & 2=
(c - x) * (c - x) =
c * (c - x) - x * (c - x) =
c&2 - cx - cx + x&2 =
c&2 - 2cx + x&2

Also, if it was (c + x) & 2, the answer would be c&2 +2cx + x&2, notice that it is 2cx is not negative now. Most people have this memorized, that's why he didn't bother to explain it.

[griftorifto]

@turquoiseguy Pythagoras theorem(s) to get step before that. Then multiplied it out and moved formula around

[deadlyvirtues]

Try to count how many times he says "squared" in this video.

[simonshugar]

The triangle obviously has an area of 0. The formula says that the area of the triangle is 1.11803398875...

[ahmedbaig]

I have loaded few videos of area of Triangle, Herons Formula.

[neoproletar]

You just did the math wrong. With a=1, b=2, c=3, the formula gives an area of zero as expected.

[simonshugar]

This formula is not right. If you have side lengths 1, 2, and 3 on a triangle, it will have no area. Sides 1 and 2 put together = 3. I used the formula that you ended with for this video and substituted these numbers for the letters. a = 1, b = 2, and c = 3. The area of my "triangle" turned out being 1.11803398875... I did it on a calculator.

[Slothd]

Why kids love cinnamon toast crunch? Why kids like apple jacks when they don't taste like apples?

[bingflop]

im doing a directed investigation on this and i am in yr 11 (16 yrs old)

[bradq]

is there anything this guy doesn't know?