Why x*0 = x

[ErGingerbreadMandude]

Consider P = mv
Consider v = 0

What I was taught was this:

When v = 0,
P = m * v
P = m * 0
P = 0 [Since any number * 0 = 0]
And thus P becomes 0.

Well, I'm saying that what I was taught was wrong.
This is what I think is happening(I have broken it down to what actually is happening):

When v = 0,
P = m * v
P = m [Because 0 literally means nothing. Therefore if v were 0 then it would mean that v doesn't exist in the statement,logically.Also because when the velocity of a rolling ball becomes 0 it means that the ball carries no momentum,it doesn't mean the ball carries no mass.]
m = m  [Because P=m is a meaningless statement as far as momentum is concerned.It is also a wrong statement as P is not equal to m. m is equal to m.]
I mean like, think about it, If a ball lost it's velocity the momentum becomes zero not the mass.

Now consider this:

6 = 3 * 2
6 = 3 * 0
6 = 3
3 = 3

Therefore:  x * 0 = x.

Do I win cookies?

[Cyberman]

6=3?

[LastPoet]

[Alex K]

That's not how multiplication works in algebraic fields. I have nothing further to say on the matter

[houseofcantor]

That ringing in your ears is your brain calling for help. 

[LastPoet]

[Longhorn]

Firstly, you CANNOT skip an element in multiplication. If v= -1, would you skip it too because it doesn't exist? That's nonsense. You can't do that.

Secondly, m*v=P, v=0, means that P=0, meaning m*v=0, not m=0, IOW, v being equal to zero has nothing to say about the value of m in m*v.

And you said it yourself, if the velocity is zero the momentum is zero, not the mass, but the momentum is mass multiplied by velocity. The rest of your post is nonsensical and doesn't follow.

In short, that's not how multiplication works

[brewer]

Turn it into a geek t-shirt billboard and cash in. Then x * 0 = $

[Tiberius]

If you throw 1 ball 0 times, how many balls have been thrown?

That's all P = mv means.
m = number of balls
v = number of times you throw each ball
P = total number of times you throw a ball

So if your math was correct, which it isn't, you are saying that when you throw 10 balls 0 times, you've thrown 10 balls, when in reality you haven't thrown any of them.

You can't just disregard a variable in algebra just because it's value is 0. The variable still has meaning, it's still important.

[BrianSoddingBoru4]

When I was 10 or 11 (I think), there was a girl in the class who couldn't grasp that division by 0 wouldn't work. The teacher was impressively patient with her, but she still didn't grasp it. The teacher then did something which I thought was brilliant.

He called the girl up to the front, then asked 10 of us to bring our textbooks up and place them on the desk. He then asked the girl to create a single pile out of the books. She did, and the teacher told her, 'Ok, that's 10 divided by 1, and it gets us 10 books in one pile. Now, divide the books into two even piles.' She did, and he said, 'That's 10 divided by 2, which gets us 5 books in each pile. With me so far?' She was, and he had her divide the books into five even piles, explaining, 'Now, we've divided the 10 books by 5 piles, which gets us 2 books each. Now, divide the books into zero piles.' She looked at him for a second or two, and I swear I remember seeing the light dawn on her face.

With the right teacher, anyone can be taught.

Boru