-5 - 8 = would i add ? and keep the negative sign how about -5 + -8 = what should i do then?

Question

I know how to do it its just that the signs negative and positive that get me messed up if any body could explain the signs rule and when you have to do the opposite and subtract or add. And No, i don't go to school i dropped out and i'm in this one program trying to finish high school if you guys would help me it would be nice at least im trying right its very hard for me now trying to get back on track.

Answer 1

think about it this way. minus five AND minus eight
not minus five (minus) positive 8.
so, minus 5 and minus 8 = minus 13
positive 5 and positive 8 = positive 13
minus 5 and positve 8= positive 3
positive 5 and minus 8= minus 3
Hope that helps

Answer 2

-5 - 8. The - sign before the 5 is a negative sign.The - between the -5 and 8 is a sign of operation, subtraction. A plus 8 is to be subtracted from a negative 5. When a number is being subtracted, its sign must be changed to the opposite of what it was, so the 8 becomes a negative 8. Now the problem
is -5 -8. When the signs are the same, add the absolute values and place the common sign which is negative in front of the answer. -5 -8= -13. The difference between -5 and 8 is -13.

Answer 3

I always think of these things on a scale:

Draw a horizontal straight line on a piece of paper.

Write zero in the middle

Moving to the left is negative (-) and moving to the right is positive (+).

So -5 -8 means: Move to the left of the zero by making 5 little pencil marks on the line. You're now at minus 5. (OK so far) then starting from where you finished up move another 8 marks (-8) to the left. Now count the marks from the zero and you should be 13 marks to the left of the zero which is.... -13. So -5 -8 = -13

Now try -5 +8:

5 marks to the left of the zero and then 8 to the right and you'll find yourself 3 marks to the right of the zero. So -5 +8 = 3 (we should really write +3 but since most numbers we deal with are positive we don't usually write down the +).

+5 -8 is 5 to the right and 8 to the left. So +5 -8 = -3

Try these:

-1 -3
-3 -4

+4 -8
+2 +3

-3 +6
-5 +2

Just use the scale. Anything to the left is negative (-) and to the right is positive (+)

I'll show you the first one: 1 mark to the left of the zero (-1) and then another 3 marks to the left (-3) and you will find yourself at -4. So -1 -3 = -4.

After you've done these ask another question and we'll get onto the next step and move away from using the scale to doing it just with numbers and signs (+ / -)

Answer 4

Well done for trying again. Both answers are -13.
Your fist sum was 2 negatives but there is still a plus sign in front of the 8, even though it's not shown. So the sums read the same in both cases. The rule is that 2 negatives together make a positive and a negative and a positive together equal a negative. For example, your sum read -5-8, we assume that it reads -5-+8, therefore the 2 signs together make a negative. \if your sum had read -5+8, it would then mean -5++8, in which case you would have 2 positives to gether and would add them equalling -5+8 which would have given you the answer 3.

Answer 5

Whenever you have the same sign throughout (say, - or +),

you add up all the numbers and put before the total the sign that appears uniformly.

e.g., -3-8-5-2 = -18
+3+8+5+2 = +18

When you have a mixture of (-) and (+) signs, what you do is, add up the numbers of same sign separately (all positive numbers on one side and all the negative numbers on the other side. Put the appropriate sign before each total). Subtract the smaller total from the bigger total. Just before the resultant answer, put the sign of the bigger total.

e.g., -3 +8 -5 +2 = ?

Step1: Sum up the total of (+) numbers:

8 and 2 = +10

Step2: Sum up the total of (-) numbers:

5 and 3 = -8

Step3: Subtract the smaller total, namely, (-)8 from the bigger total, namely, (+)10:

10 - 8 = 2

Step4: Before the above answer put the sign of the bigger total,
namely, +. Hence the answer is +2.

Answer 6

Hi this is not at al a prob.

Ex: If u have borrowed money say '5 lacs' that means u will have to pay '5 lacs' than thats -5 for u. Now, in that if u borrow somemore say '8 lac' than tats -8 for u. Now, if someone asks u how much u have borrowed than the answer will be '-13'... How?

(-5) + (-8) = -5 - 8(because when minus plus signs are multiplied minus sign stays) = -13. This is because when u were intially negative and if someone take away from u more than u become more negative.

You can also view it as -5 - 8 = -(5+8) = -13, because - sign being common is taken out so only plus remains inside the bracket.

Therefore the two expressions u have asked are one and the same.

Rules: 1) (-) + (-) = (-)
2) (+) + (-) = sign of the greater number will stay, like its 9 - 7 = 2 because sign 9 will stay as it is bigger.

3) (-)*(-) = +, when minus minus are multipled it becomes +
4) (-)/(-) = +, when minus minus are divded it becomes +

5) (-)*(+) = -, when minus and plus are mltiplied it becomes -
6) (-)/(+)= -, when minus and plus are multipled it becomes -

Hence, in short, during multiplication and division when two opposite signs come together minus will remain, and if two same signs are multiplied it becomes +.

While doing addition and subtration the sign of the bigger number remains.

I hope this will help you in learning ur concepts well.

Answer 7

Its great that you are trying again. Lets see if I can help with another "borrowing" analogy
You have -5-8=?
Now try to think of negatives as if you were borrowing. For this problem, anytime you see the negative sign, whether you think it is for the negative or even for subtraction think I am borrowing this much.
Start from the beginning, -5, means you already owe five. Then, you see another negative sign, so borrow that much more, eight. How much do you owe? 13, where owing thirteen means= -13

Now look at it from another angle: -5+-8=?
You owe five.
Plus means and
you borrow eight
you now owe 13, and to mathematically write "you owe" we put a negative so it is -13.

good luck

Answer 8

The best think to do is to add the plus between the number everytime. As adding is more natural that subtracting (at least in my case), you get adding everytime and then do it 'forward' for adding positive numbers and 'backward' for adding negatives.

So:

(-5)+(-8)=-13
5+(-8)=-3
(-5)+8=3

Answer 9

-5-8 = -1*(5+8) = -1*13 = -13

-5+8 = 8-5 = 3

Answer 10

Okay you have 2 add. Look if it same sign on both numbers then add(positive and a positive, negative and a negative) or subtract. In multiplication if similar signs are present then put a positive sign else negative sign after multiplying

Answer 11

Look at the signs between the 2 numbers and follow this simple rule:
minus = minus
plus=plus
minus and plus = minus
plus and plus = plus
minus and minus = plus

Then imagine that there is a line with 0 in the middle.
-13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8

For -5-8 you start at -5, and because there is just one minus between the 5 and 8 you minus 8 (move left on the line) to get to minus -13

For -5+-8 you start at -5, and because there is a plus and minus between the 5 and 8 you minus 8 (move left on the line) to get to minus -13

For -5 + 8 you start at -5, and because there is just a plus between the 5 and 8 you add 8 (move right on the line) to get to +3

When you multiply 2 numbers...e.g. -5 x -8 you follow a similar rule

plus x plus = plus
minus x minus = plus
plus x minus = minus
minus x plus = minus

so -5 x -8 would = 40
or -5 x 8 would = -40
or 5 x -8 would = -40
or 5 x 8 would = 40


The way I remembered the double negative equals positive rule is with words....e.g.

I don't want to eat = I don't want to eat
I don't not want to eat(double negative) = I want to eat

Good luck! I know it's tough to study on your own.