Math Question, Grade 9 Math?

To do the first part, take the absolute value of both values. If the larger number (absolute value) is negative, then your answer will be negative. Likewise, if it is positive, your answer will be positive.

Example) -8, 4

l-8l > l4l Which means the value of negative eight and four is in the negative set of numbers.

For dividing and multiplying, if one value is negative then the outcome is also negative.

Example) 6, -4

6*-4 = -24

When adding two rational numbers where one is positive and one is negative, if the positive rational number is greater than the negative one, then the answer will be positive. Vise-versa if the negative number is bigger. Imagine two numbers on a number line, (a negative and a positive). We'll use -2 and 1. Now start at 1 and add -2 (this is the same as subtracting 2). You go 2 to the left and end up on -1. This is because you went to the left (negative) a greater distance than you were towards the right (positive). Since 2 is greater than 1, going towards the negative side from the positive 1 will make you end up in the negative side. Had our numbers been -1 and 2 and we added -1 to 2, we would still stay in the positive side, 1. 1 is less and 2 so going to the left by 1 will not bring positive 2 to the negative side.

When multiplying or dividing two rational number, if one of the two numbers is negative, then your answer will also be negative. If both are negative, then your answer will be positive. All a negative number does in multiplication/division is flips the sign. So if you had 1 x -2, you get -2. If you had -1 x -2, you get 2. The negative from the 2 flips the sign of the -1. (By flipping, I mean going from negative to positive or vice-versa). So if you had 1 x -2 x 3, your answer would be -6. If you have an even number of negative signs, then your answer will be positive. If you have an odd number of negative signs, your answer will be negative. The same rules apply for division except you are dividing (which is essentially the same as multiplying).

Well, to determine if the answer is positive, You must check to see if the positive number you are adding to the negative number is larger or vice versa.

Example: -23/4 + 25/8 = Since 25 > 23, we would assume that 25/8 is the answer, but it is not. We must now check the denominators. Since 4 is closer to 1 than 8 is, now we are in a bit of a jam. We must now simplify each fraction. -23/4 = -5.75 and 25/8 = 3.125.

In the end the negative number is the larger number, so we will get a negative answer.

Rational Numbers - http://en.wikipedia.org/wiki/Rational_number

Always check the denominator of the fraction. The fraction that has a denominator closer to 1 is usually the larger number (considering the numerator is equal to or greater than the fraction that has a higher denominator).

if both numbers are positive or negative ,the result remains the same .if not ,the number which has the larger absolute value decide the symbol of the result .

in multiplication and division .if both numbers are positive or negative ,the result is positive .if one if positive and the other is negative ,the result is negative .