Why does double negative egual positive?

Question

i know it does, but i don't totally understand why!

Answer 1

Listen to how a double negative statement sounds, the double negative adds a layer of ambiguity to the statement when absolute clarity is needed, which implys the object of the conversation has done to it, exactly the opposite of what the speaker intended to say.
So to say "I ain't never going to drink Coffee" implies the speaker is infact going to drink coffee. It's as good as saying "I will always drink Coffee".

Answer 2

Draw a number line from -5 to +5 with 0 in the middle.
Now if you wanted to find the distance from +4 to +2 you would subtract +2 from +4 and get 2. 4 - (+2) = 2.

Now suppose you wanted to know the distance from +4 to - 2.
You can count the spaces on you r nunber line ansd see that it is 6 units. So 4 - (-2) = 6. So clearly the two minuses must become a plus or our numbering system would not work.

Consider that anything divided by itself is one. So, -1/-1 = 1.

This shows again that two minuses = a positive.

Answer 3

Consider the following examples
Example 1
5 - 2
To answer this, think of these two numbers on the number line and ask how many steps from 2 to 5. The answer is 3 steps to the right so 5 - 2 = 3
Example 2
5 - (-2)
To answer this, think how many steps from (-2) to 5.The answer is 7 steps right.This is obtained by saying 5-(-2) = 5 + 2 = 7

Hope these two examples might help.

Answer 4

The best answer I've heard is this:

Mathematicians a long time ago agreed to do maths in this way.

Apparently there a huge debate at the time as to whether a negative number could even exist.

It would appear that the ones who thought negative numbers could exist won the argument.

And this rule is a side effect.

Answer 5

For the most part, you are only going to have to deal with fields in your typical education. The set of real numbers is a field. And these fields have to satisfy certain properties in order to be considered fields. One of those properties is -1 * (x) = -x. This can be read "negative one times some quantity 'x' is equal to the opposite of 'x'." Now 'x' can be any quantity in the set of real numbers. If you say you want -1 = x, then you can just plug it into our statement. -1 * (-1) = -(-1) OR "negative one times negative one is equal to the opposite of negative one." The opposite of 'negative' is 'positive' so you have 1 as your final answer.

Answer 6

You should have paid more attention during your maths lesson.

Without a piece of paper this might be hard to explain but let's give it a try.

First the basic mathematical rules are

+ and a + is always a PLUS
+ and a - is always a MINUS
- and a + is always a MINUS
- and a - is always a PLUS

ERRRR...ok..er...just imagine a row of numbers going from left to right 1,2,3,4,5,6,7,8,9 if you tale away a number you would go from right to left so 9 minus 4 = 5 (with me so far :-)

Once you get to zero and deduct a number you still go from right to left so Zero MINUS 5 = - 5 (still with me.)

NOW here's the bit that frys your brain -

Once you get into a minus number the rule reverses so -5 MINUS 5 you go back to the right again and so you get to zero.

Does that help....fried my brain trying to explain it..:-(((

Answer 7

It's one of those questions like 'why is the world round?' I know what you mean - I always wanna understand where everything comes from, but I think in this instance you just have to accept it! I don't know that there's a popularly known reason for it! Let me know if you find one though!!

Answer 8

Because a negative reverses the next sign.

Answer 9

because a negative sign is read as "opposite" Example: the opposite of 2 is -2. So.. Two opposites make a positive.

Answer 10

if yo times a negative by a negative the negatives cancel .... so it is a posahe resin is it is a mathamatocal rule the prufe for wich can be found on the internet