Since the division problem turned out to be so much fun the multiplication and division one. Here's another one that

因為切割問題變為十分有趣的乘除，這有另外一題

Somebody pointed out to me

某人提供給我的

so I think it's

我想是這樣的:

just I don't know let's take a look so

好吧我不知道，我們來看一下

So negative twenty well

好所以..-20...好

That certainly equals negative 20 no arguments there, I think

我想這個等式應該沒有人反對

Let's break up negative 20. I'm gonna break it up on the left

我們把-20拆開 我先拆左邊的

I think I'm gonna write that as 16 minus 36 certainly you still get negative 20 there and

我想我將會將它寫成16-36的型態，如此結果仍為-20

On the right side. I'm gonna write that as 25

至於右邊的，我會拆成25

minus 45 okay, so

減掉45，所以

Now I'm gonna rewrite things a little bit more

現在，我要把算式再展開更廣

I'm gonna rewrite 16 is 4 squared and then I'm Gonna rewrite 36 as 4 times 9

我要把16變成4的平方、36變成4乘以9

On the right side. I'm gonna rewrite 25 as just 5 squared and then I'm Gonna rewrite 45 as

右邊，我要將25變為5的平方、45則變為

5 times 9 and

5乘以9

Alright, well, I think what I'm gonna. Do now is I'm Gonna add

好，我想一下接下來我要怎麼做。

To both sides and the number that I'm gonna add to both sides is I'm Gonna add 81 over 4

我現在要在兩邊同加81/4

All right, so that's what we've got so far

好吧，這是我們目前得到的

well actually I think we can factor this now a little bit, so

事實上，我覺得我們現在可以分解一下它

we can do a couple things here and

我們可以把東西結合在一起

You know you can you can check that this all works, so I'm gonna leave the 4 squared alone

你可以觀察一下整個算式，我要把4平方留著

We can just rewrite

我們可以改寫成

4/9 pretty easily, I'm Gonna write that as 2 Times 4

4/9，很簡單。後面的改成2乘以4

times 9 over 2 so I'm just breaking up the 4 over 9 here a little bit and

再乘以9/2。我在試圖分解4/9

then I'm Gonna rewrite 81 over 4 as

接著再把81/4分解成

9 Over 2

9/2

Squared on the right side. I'm gonna do the same thing. So we've got 5 squared

的平方。我要做跟剛剛一樣的事，所以我們留著5平方

What I'm gonna do here is I'm gonna write this as 2 times 5

將後面的部分改為2乘以5

Times 9 over 2 and then plus 9 over 2 squared

在乘以9/2，最後加上9/2的平方

Okay, so you know we're just basically just the Tube and the nine halves would cancel hey give us back our or our nine that

好，所以現在你知道我們在算式中整理出了9/2

We had up there so all right so far so good well the reason why we do. This is this now factors nicely

以及到目前為止我們做這些的原因

this actually factors as 4 minus 9 over 2

接下來，我們將算式整理為4減9/2

Times 4 minus 9 over 2

乘以4減9/2

And the right side is gonna factor as 5 5 minus 9 over 2

而右邊則整理為5減9/2

Times 5 minus 9 over 2

乘以5減9/2

All right, well

好吧

What that tells us is well. We've got 4 minus 9 over 2

所以，我們得到4減9/2

squared that equals

的平方會等於

5 minus 9 Over 2

5減9/2

Squared and now well that means 4 minus 9 over 2 equals 5 minus

的平方。同時也代表4減9/2會等於5減

9 over 2 and

9/2

well, we could add 9 over 2 to both sides so that tells us that 4 equals 5 and well if we subtract 4 from

最後，我們可以將9/2放在同一邊、4和5在同一邊

both sides

兩邊整理完後

That now tells us that 0 equals 1 so proof complete

我們就能得到0等於1，故得證