subtracting negatives and positives???

Question

- 5.95 - (- 5.1 - -5.1)
- 10.2 - +10.2

Answer 1

5.95 - (- 5.1 - -5.1)
= - 5.95 - (- 5.1 + 5.1)
=- 5.95 - (0)
=- 5.95

-10.2 - +10.2
=- 10.2 - 10.2
=-20.4

Answer 2

first know that a - times a - = a +
also a + times a + = + or when the signs are the same the answer is positive.
and when the signs are different +times- and -times + the answer is - .


- 5.95 - (- 5.1 - -5.1)=

this becomes
- 5.95 - (- 5.1 + 5.1) I changed -- to + then
- 5.95 - (- 5.1 +5.1) becomes - 5.95 + 5.1 -5.1
I multiplied the - outside the parenthesis by what is inside according to the rules mentioned.
Now just add and subtract everything like normal to get -5.95.

- 10.2 - +10.2= - 10.2 -10.2 = -20.4
Here I changed the -+ to a single - ( see the rules) the two negative numbers add. Think of it like this, -10.2 is money you owe (negative means you owe the money and don't have it) so you owe 10.2 and another 10.2 then you owe 20.4 or -20.4. In terms of dollars this should make a lot of sense.

Answer 3

Rule Two +'s make a +; Two -'s make a +; and one + and one - make a -.
Reduce the + & - signs to 1 sign:
+A * (+B) is the same as A*B
A++++++B is the same as A+B {any number of + signs reduce to one.....or none since ++Q is Q)
A - - B is A+B
A - - - B is A - B
so an even number of - signs infront of a number reduce to + (or nothing since - - A is +A which is A)
and an odd number of minuses reduce to one minus
A - - - - -B is A - B
the reason is the -(-B) is +B because the - operator can always be replaced by the + operator AND with the "mulitply by minus one operator". e.g. A - B = A + (-1)*B and -1*B = - B so A - B = A+ (-B)
ANother way to put it:
Adding a negative number is the same as Subtracting the positive of that number. And vice versa subtracting a positive is the same as adding the negative.

Answer 4

- 5.95 - (- 5.1 - [- 5.1])
- 5.95 - (- 5.1 + 5.1)
- 5.95 - (0)
- 5.95 - 0
- 5.95 answer

- 10.2 - (10.2)
- 10.2 - 10.2
- 20.4 answer