why do you add when you subtract a negative?
401863
7 - (-8) is 7+8  not 7+9.\n\nThe rule is an even number of negative signs gives a positive.  An odd number of negative signs gives a negative.\n\nThink of a line representing a coordinate axis. Put zero on the line. Then put on 1,2,3, etc. Each of them goes to the right.  Now put on -1, -2, -3, etc. Each of them goes to the left of where zero is.  now, what is the distance from +1 to +3.  It is 2, that is 3-1.  Now what is the distance from 1 to -3.  Count the spaces. It is 4. That is 1- (-3) = 1+3=4.\nFurther what is the distance between -1 and -3. Two spaces 2.  That is -1 - (_3) = -1 +3 = 2.
78925
well, you look at the biggest digit, not including the sign.  lets say it is -7-5.  7 would be the biggest.  Then, see if its subtract or add.  This is add.  It has to be negative, since its a -7.  Another example is 7-9.  9 is the biggest, and since its a negative, the answer is a negative. One last one.  -2+9.  9 is the biggest, and since its possitive, the answer is positive.
615376
there are several methods,\n\nalmost all mathematical calculations like add, subtraction...... have many ways to calculate......\n\ncheck the website below to find alternate ways to calculate
845669
2x-3... because 2x means twice a number, and if you want 3 less than that, you would subtract 3.
327077
generally, you combine like terms and then subtract the same thing from both sides and/or divide both sides by the same thing.  but that may b 2 vague to help much.  i need a specific question.
27071
The problem with negative numbers is that they don't actually exist.  We talk about negative values but it's technically impossible to have a negative amount of anything.\n\nI've found the easiest way to make students understand negatives is to talk about what happens when you owe a certain amount.\n\nFor instance, if I have four apples and you want to get five apples from me, I can give you four but then I have no more.  Therefore, I will owe you one apple.  This apple - which I do not have but which I owe you - is like a negative number.\n\nWhen all else fails, go for the number line.  Numbers extend on to infinity in BOTH directions, from zero and up, and down as well.  If your eight year old can understand infinity, negatives shouldn't be too hard.\n\nNegative numbers, by the way, are generally sixth-grade material.  Don't be frustrated if your child doesn't understand yet!  Some things will take time.
834363
here are some tips on how to add/subtract/multiply/divide signed numbers.\n\nmultiplication: when multiplying positive to positive the ans is positive\nwhen multiplying positive to negative, then ans is negative\nwhen multiplying negative to negative the ans is negative.\nif you face a prob like this:\n(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)(-1)=?\nno sweat. just count the number of negative signs and multiply all the coefficients. if the number of negative signs is an odd number, then your answer is negative, but if the number of negative signs equal an even number, the ans is positive. so in this case, there are 23 negative signs so the ans is negative.\n\ndivision: same principle as multiplication but this time you divide the coefficients\n\nadd: when adding two integers, if the number attached to the negative number is greater than the number it is being added to, simply subtract and just add a negative sign to the number but if the number attached to the negative number is lesser than the number it is being added to, simply subtract and dont add a negative sign to the number.\nex. -5+4=-1\n5+(-4)=1\n\nsubtraction: when faced with a problem similar to this:\n5-(-4)=?, we need to remember that it is the same as \n5-1(-4) so it is like multiplying -1 t0 -4.\n\nthe principle behind addition and subtraction:\nif you say: -5+4, it means that you are moving 5 units to the left from zero on the number line and four units to the right of five.
520921
The (x-3)s cancel out because they will produce the same answer for all values of x.\n\n(x-5)/(5-x) produces an answer of -1 because they'll always be the opposite (negative) answer for all values of x.\n\nThe answer is -1
944997
you divide or multiply by a negative numberand the sign of inequality flips
928992
It is not a + sign underlined.It is plus and minus sign put together indicating that the result is either positive(+) or negative(-).In fact when when we find out a square root of any number say 16,the answer may be +4 or -4 because +4^2is 16 and -4^2 is also 16.Therefore square root of 16 is plus-minus 4 that is eithr plus 4 or minus 4.
784978
Depends on what calculator you use...some are +/- and some are just -. So it depends...Sometimes you have to push 2nd function to get it.
678092
Adding a negative number is the same thing as subtracting a positive number. Picture a number line. +2 means to move right 2 spaces. -4 means to move left 4 spaces. You end up on the left side 2 spaces from 0. This is -2.
294368
4-4\nI don't know if - means minus or not.
200519
+/- 1\n\nThe answer is not 1, because -1 * -1 = 1 also.
1007006
add or subtract 1\n\nor else subtract the S at the begining of Seven
89171
You cant just add or substract whatever is left. You invalidate the function of "division" by partially dividing then filling in the rest of the numerator. The number left over after something has been divided is called the modulo, and is useful for programming functions. You cant do an incomplete division(only dividing 20/5 instead of the 2/5 also) and then speculate as to why it cant be negative when doing a full division. It invalidates the definition.
491966
Negative plus negative is ALWAYS negative.\n(-5) + (-3) = -8\n\nNegative minus negative may be negative, positive, or zero.\n(-5) - (-3) = (-5) + 3 = -2\n(-5) - (-5) = (-5) + 5 = 0\n(-5) - (-8) = (-5) + 8 = 3\n\nNegative plus positive works the same as negative minus negative. See the examples above.