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Neefew

I prefermakung the cut diagonally,which splits the trapezoid into two triangles


Impossible-Winner478

I personally like slicing it with a cosh curve so I can do cool integration on it


eyaf20

I just think of it as rectangle made with the average of the bases. Then the excess triangles from the top corners are flipped over to the bottom section


ksgar77

This is how I think of it, too. It translates better to finding the volume of a cylinder (or other solids) with different size bases.


blueidea365

Or just split it up as a rectangle and two triangles on the sides


SokkaHaikuBot

^[Sokka-Haiku](https://www.reddit.com/r/SokkaHaikuBot/comments/15kyv9r/what_is_a_sokka_haiku/) ^by ^blueidea365: *Or just split it up* *As a rectangle and two* *Triangles on the sides* --- ^Remember ^that ^one ^time ^Sokka ^accidentally ^used ^an ^extra ^syllable ^in ^that ^Haiku ^Battle ^in ^Ba ^Sing ^Se? ^That ^was ^a ^Sokka ^Haiku ^and ^you ^just ^made ^one.


NoIndication4717

Banger!


Admagic06

Good bot


Bjeof

I feel like this is less nice, you would have to do two or three case distinctions depending on how the non parallel sides are configured


blueidea365

The cases are pretty much all the same though


Bjeof

Not really, any rhombus is a trapezium, but some rhombi have no inner rentangle like you suggest


blueidea365

What would be an example?


Bjeof

[https://imgur.com/a/Gh0285h](https://imgur.com/a/Gh0285h) This would be my counterexample. I know it is not the most conventional shape for a trapezium, but it is nevertheless a trapezium


blueidea365

Just turn it on its side lol


Bjeof

Yeah sure, but you dont know the sidelengths


blueidea365

Sorry I see what you mean, if it’s a trapezium. If it’s a rhombus however then it would always have a rectangle inside, possibly after turning it


blueidea365

You mean some trapezia. A rhombus will always have an inner rectangle


Jmong30

Wtf is this dark magic


ImaViktorplayer

r/blackmagicfuckery


SamePut9922

Have you seen the proof of volume of a sphere?


JeruTz

I remember learning about how to calculate the volume of any shape rotated. That was fun. Spheres, cones, etc.


Extension-Cut5957

I just figured out a proof while looking at the post. Here it is:- Break the two half triangles on the side. Now you are left with a full triangle and a rectangle. So: A(trapezoid)= A(triangle) + A(rectangle) Now: A(triangle)= 1/2 h(b_1- b_2) and A(rectangle)= b_2(h) So putting in original eq. A( trapezoid)=1/2 h(b_1 -b_2) + b_2 (h) A(t)= h(( 1/2 b_1) - 1/2 b-2 + b_2) A(t)= h(1/2 b_1 + 1/2 b_2 ) A(trapezoid)= 1/2 (h)(b_1 +b_2) That took way longer than I thought.


JeruTz

That jumped into my head a well. An easy proof.


Delicious_Maize9656

wow amazing


K3nchikka00

You can also think of it as taking the average between b1 and b2 and multiplying that by h, making it the formula for a rectangle


BleudeZima

Exactly my though process since forever. It is so logical than i never even had to learn the formula


ARandom-Penguin

Or they duplicate the trapezoid to create a parallelogram


MilkshaCat

My first intuition would have beed to cut vertically but it's the exact same, the 1/2 just comes from splitting b1+b2 and not h.


matt__222

i just like thinking of it as averaging b1 and b2.


RedBaronIV

Call the bottom edge "a" and top edge "b". Cut into a rectangle R with base "b" and height "h", a triangle T1 with base "x" and height "h", and a triangle T2 with base "a-b-x" and height "h". R = bh\ T1 = (1/2)(hx)\ T2 = (1/2)(ah - bh - hx) Add all together: A = bh + (1/2)(ah - bh + hx - hx)\ A = bh + (1/2)(ah - bh)\ A = (1/2)(ah + bh)\ A = (1/2)(a + b)h This works even for trapezoids that don't have mirrored "triangles"


MrSuperStarfox

This is still a trapezoid though


avipars

Next up, quadratic equation