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homework

homework

ok here is my problem if negative times a negative equals a postive then what would negative times a postive be alos if the postive or negative if bigger for ex -5+2=would equal -7 right or wrong .
7 REPLIES 7

homework

>>what would negative times a postive be

A negative times a positive will also be NEGATIVE

>>alos if the postive or negative if bigger for ex -5+2=would equal -7 right or wrong .

If a negative 5 plus a negative 2 is -7, or
-5+(-2)=-5-2=-7
IF a negative 5 plus 2 is -3, or -5+2=-3

homework

Don't get times (multiplication) and plus(addition) mixed up. The product of a negative and a positive number is a negative number. The sum of a negative and a postive number will have the sign of the number with the larger magnitude, and a magnitude which is the difference between the magnitudes. -5+2=-3. You can consider positive and negative to be opposite directions. So when going five in the negative direction and then two in the positive direction the two positive units cancel out two of the negative units. Leaving three negative units.

Tom Gutman

homework

ok i sorta get that better but what about divison are the negatives and postives different there to?

homework

With respect to signs division follows the same rules as multiplication.

This comes from one of the ways of thinking about division. (a/b) can be defined as a*(1/b) (or b-1, depending on your preferred notation) where 1/b is the multiplicative inverse (reciprocal) of b. Since the product of a number and it's reciprocal is positive (it is specifically one, by definition) a number and its reciprocal must have the same sign.

Tom Gutman

homework

what? i did not mean that i meant when u add a negative plus a postive u will get a negative right but what about multiplying and dividing are there rules for that to ?

homework

On 9/24/2003 6:21:01 PM, sweetnsour wrote:
>what? i did not mean that i
>meant when u add a negative
>plus a postive u will get a
>negative right but what about
>multiplying and dividing are
>there rules for that to ?

Yes, as one might possibly suspect. if the signs are the same, the resultant is a positive number, while if the signs are different the resultant is a negative number

TTFN,
Eden

homework

No, when you add a positive and a negative you can get a positive or a negative result. Depends on which number has the greater magnitude, as described in my earlier posting. Multiplication and division follow a different rule, but the same for both. If the signs are the same (a positive times a positive or a negative times a negative) the result is a positive. If the signs are different (a positive times a negative or a negative times a positive) the result is a negative.

Tom Gutman
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