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

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Part 1 of the proof of Heron's Formula
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[@griftorifto2]

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!

[@piyushk.3754]

Where are u now O my god 9 years ago

[@GulshuPulshu]

@@piyushk.3754 Probably in JPL making rocket engines for NASA ... that would fly the SLS all the way to the moon and back ... (Artemis mission)

[@aguyontheinternet8436]

I was able to make it this far on my own. However, simplifying the formula I made(the one at the end of the video) into heron's formula, was something I could not do on my own. Just couldn't understand how

[@mashupstyles2389]

Thank you ..... you simplified the last step! :D

[@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.

[@lashamamaladze175]

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 ;)

[@narendrapratapsinghsengar5030]

Awesome explanation

[@ahmedattaalla8120]

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

[@PreCalculusRocks]

Dang.. that's pretty awesome! :)

[@ahmedbaig7279]

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.

[@simonshugar1651]

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

[@redjr242]

KZbin 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.

[@ayushpatro]

really thumps upp!!!!!!!!!!!!

[@MaryDeioma]

Please provide a link to the calculator application?

[@TheMusicalTech]

Which software you use for making videos?

[@kushshrivastava6894]

How to download the calculator you used ?👌

[@griftorifto2]

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

[@7deadlyvirtues]

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

[@mashupstyles2389]

Don't have time for that!

[@lurker784]

Tom Walker MAHAHAHHA

[@iyappansriram9854]

2326 times Holy S+it

[@divyoroy9056]

Awesomesauce 1409 What a nerd

[@ahmedbaig7279]

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

[@simonshugar1651]

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

[@MrPcadler]

Use triangle C=3, A=2, B=1. So the square root of this times 1/2 C, which would be x 1.5. The square root of A^2-(C^2+A^2-B^2/2C)^2 .So 4-9(9+4-1)/(6))^2. so 4-(12/6)^2. 4-(2)^2= 4-4=0. 1.5 x 0 is 0. Simon, your probably some 6th grade mathematician who just got a calculator from the 99 cent store.

[@MrPcadler]

And yes, I made typos, math on the computer is hard. There is not supposed to be a 9 in front of (9+4-1

[@mauk2009]

Phillip Adler A triangle with sides of lengths 1, 2, 3 its impossible because 1+2=3 and "Given a triangle ABC, the sum of the lengths of any two sides of the triangle is greater than the length of the third side."

[@Isaack297]

what about the plus minus sign ?

[@MuiYuDoTheLoo]

hi 🥳

[@joshua1auhsoj]

this rules

[@neoproletar]

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

[@divyoroy9056]

Jaroslav Hajek ur actually so dumb there’s no real triangle with those side lengths.

[@aaronwang9817]

@@divyoroy9056 A "triangle" with those side lengths would become a 1-dimensional line, which would have area 0. This shows that the formula works for "triangles" with odd side lengths, and goes to show the consistencies with math, just like how sin and cos work for angles larger than 90 degrees. That is not dumb, but in fact, good, as it proves that the formula is consistent.

[@ptechglobal4553]

I want proof of A×B=B×A

[@Astroverted.]

Man pulled up with the calci💀☕

[@Sloth7d]

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

[@zondaken]

software?

[@simonshugar1651]

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.

[@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?

[@ahmedattaalla8120]

Never mind i see what u mean but in a way im still right

[@charlesrebutazo2768]

I'm here because of grades

[@JCTronia]

5 year olds

[@anoirtrabelsi8645]

no !!!!!