Best Answer

Because a negative negative is the same a a positive, and because of the definition of subtraction and addition.

Q: Why when subtracting a negative number must you change the subtraction sign to an addition sign?

Write your answer...

Submit

Still have questions?

Continue Learning about Other Math

When subtracting negative numbers change the subtraction sign to a plus and change the second number (which would appear to be positive) to a negative. ex. -14 - 7=?/-14 + -7= -21 When adding negative numbers just add them as they appear. ex. -2 + -5= -7

Subtracting fractions are similar to subtracting regular numbers. What my teacher has taught me was to change the subtraction sign to an addition sign and make the second fraction negative. For example, if I had 4/3 - 3/4, I would change the subtraction sign to a + sign, thus making it 4/3 + -3/4, making it equal 1/4 (it's easier to remember it this way: Same Change Change). Hope this helped!

make it a '+ negative number'. Example: 6 - 7 = -1 6 + (-7) = -1

if you subtract a negative from a positive, you get a positive. subtracting a negative number is like addition, because the subtraction of a "negative," or opposite, results in a "double negative..." For example, 2 - (-5) = 7. It is no coincidence that a "negative" sign and a "subtraction" sign look the same...THEY MEAN THE SAME THING. In terms of money, with which we are all familiar, subtracting a negative is like subtracting a debt. For example, if you borrow $50 to buy a game, your account balance is "-50" because you owe that much money. However, if you pay off $5 a week, after the first week, you've subtracted $5 from the debt that you owe... - 50 - (-5) = 45. Even if you need to rewrite the subtraction problem so that it appears as an addition problem (then to which you can apply the rules for adding numbers with like & different signs), change the subtraction sign to addition, and switch the sign of the second number. {Ex: 2 - (-8) = 2 + (+8) = 10}. Pretend you're in English class... we even use "double negatives" in our everyday speech, where we negate what was just said... Ex: "we will not be having 'no homework tonight.'") In other words, sharpen your pencils, because there is, indeed, an assignment. When subtracting a negative, it's like taking the "opposite of the opposite..." which has you winding up right where you started... the opposite of a negative is a positive, so you add the positive number

To subtract a negative number, you must change the subtraction sign to an addition sign, then make the second number its opposite. Ex. (-9)-(-13) (-9)+(+13)=4

Related questions

Adding +k is the same as subtracting (-k).

no, the absolute value does not change the subtraction into addition. it does however, change the difference to positive ( if the difference is negative)

One method to subtracting a negative number Is "keep, flip, flip". First you keep the first number being lowered, then you change the subtraction sign to addition. Lastly change the negative number being subtracted to a positive number. Ex. 9-(-5)= 9+5=14

Example: -4-(-3)=? Change the subtraction sign to plus sign and change the negative three to a positive three. -4+3= -1

When subtracting negative numbers change the subtraction sign to a plus and change the second number (which would appear to be positive) to a negative. ex. -14 - 7=?/-14 + -7= -21 When adding negative numbers just add them as they appear. ex. -2 + -5= -7

Subtracting fractions are similar to subtracting regular numbers. What my teacher has taught me was to change the subtraction sign to an addition sign and make the second fraction negative. For example, if I had 4/3 - 3/4, I would change the subtraction sign to a + sign, thus making it 4/3 + -3/4, making it equal 1/4 (it's easier to remember it this way: Same Change Change). Hope this helped!

The rules for addition are as follows:The sum of two negative integers is a negative integerThe sum of two positive integers is a positive integerThe rules for subtraction are as follows:If they are two positive numbers, do it normallyIf there is a negative and a positive ,change it to addition and switch the SECOND integer sign

The same way you'd add any other negative numbers. Adding a negative is the same as subtracting, and subtracting a negative is the same as adding. (-2) + (-2) = (-4) (-2) - (-2) = 0 you are wrong if you add or subtract two negitives its always a positive dont you know your math. And the second problem you have is wrong to because when you subtract two negitives you change the sign of the secong number to positive and you change the subtraction sign to a addition sign.

make it a '+ negative number'. Example: 6 - 7 = -1 6 + (-7) = -1

6

if you subtract a negative from a positive, you get a positive. subtracting a negative number is like addition, because the subtraction of a "negative," or opposite, results in a "double negative..." For example, 2 - (-5) = 7. It is no coincidence that a "negative" sign and a "subtraction" sign look the same...THEY MEAN THE SAME THING. In terms of money, with which we are all familiar, subtracting a negative is like subtracting a debt. For example, if you borrow $50 to buy a game, your account balance is "-50" because you owe that much money. However, if you pay off $5 a week, after the first week, you've subtracted $5 from the debt that you owe... - 50 - (-5) = 45. Even if you need to rewrite the subtraction problem so that it appears as an addition problem (then to which you can apply the rules for adding numbers with like & different signs), change the subtraction sign to addition, and switch the sign of the second number. {Ex: 2 - (-8) = 2 + (+8) = 10}. Pretend you're in English class... we even use "double negatives" in our everyday speech, where we negate what was just said... Ex: "we will not be having 'no homework tonight.'") In other words, sharpen your pencils, because there is, indeed, an assignment. When subtracting a negative, it's like taking the "opposite of the opposite..." which has you winding up right where you started... the opposite of a negative is a positive, so you add the positive number

When you are subtracting a negative from a positive or a positive from a negative, you change subtraction to addition and change the sign of the next value. example: (-23)-(-12).......change it to........(-23)+12 Then you subtract the bigger number from the smaller number. Don't worry about the negative signs just pretend that the numbers are both positve. Example: 23-12=11 Then you take the sign of the biggest number. example: 23 was the bigger number and it was negative so the answer is -11 Hope this helped!