Question

-(-D)

Wha does the minus sign outside the bracket do to the -D inside the bracket?

100% serious question...lol

Answer 1

when you multiply two same signs you get positive outcome.

Answer 2

+ times + = +
- times - = +

Answer 3

and btw -(-D) is same as
-1(-D) or you can rewrite it as
\[\rm -*-D~~~ or ~~~~-1 *-D\]

Answer 4

i have a tutorial on this
check my profile

Answer 5

Yes. Nnesha is right.

What, then, is the (simplified) final result if you work on -(-D)?

-(-D) = ?? (This question is for @dehelloo.)

Answer 6

D lol ?

Answer 7

Why a negative times a negative is a positive

Answer 8

I try to conceptualize it but still don;t understand why double neg equals positive.

Answer 9

-5 x 4 = -15 -5 + -5 + -5 +-5 or -5-5-5-5

-5 x -4 = 15 but (-5)- (-5) - (-5) - (-5)

I just don;t understand why lol other than deducing that two negatives should equal a positive because -5(4+-4) = 0

Answer 10

Woops -20 lol

Answer 11

http://mathforum.org/dr.math/faq/faq.negxneg.html

Answer 12

Think of -(-5) and being 0 - (-5).

The rule of subtraction is to change the sign of the number being subtracted (called the subtrahend) and to add it to the first number.

0 - (-5) becomes 0 + (+5) = 0 + 5 = 5.

Less mathematically but perhaps more interesting.

Here's what a teacher once told me.

"Negative numbers are living in a town with 'nice' numbers. Negative numbers are bad. A minus symbol appears when a person leaves town. Therefore, -(-D) means the bad person -D is leaving town. That is a good event. Ergo, -(-D) = +D."

Answer 13

How would you use the analogy for bad/good numbers for a singular substraction for -D-D?

That there are bad people leaving bad people but it results in more bad people/numbers.

Appreciate the answers though.

Answer 14

-D -D = - (D + D) by the distributive property

- (D + D) = - (2D)

- (2D) = 0 - (2D)

Consider 2D as two good people

0 - (2D) = 0 +(-2D) = + (-2D) = -2D

Two bad people came to town and that is a bad thing.

Note that the explanation is bordering on absurdity.

Answer 15

Lol thanks for trying to help. Makes no sense but sort of does so I guess I'll just have to accept the law as fact.