By working with sums and differences, we will see that.
1) We can write the equations:
2) If both numbers have the same sign, the outcome will have that sign. If the numbers have different signs, the sign of the outcome will be that one of the number with the largest absolute value.
How to solve linear equations?
The first two problems that we need to solve are:
a - b = 11
c + 9 = d
So we just need to find two values from the given ones, if we take:
a = 5
b = -6
Then we have:
5 - (-6) = 11
And by the rule of signs:
-(-6) = 6
Then:
5 - (-6) = 5 + 6 = 11
So this is correct.
For the other equation:
c + 9 = d
Here c should be a negative number (because d can only be a single-digit number).
The remaining positive values are:
6, 7, and 8.
The remaining negative values are:
-1, -2, and -3
So we can make any of the 3 pairs:
- -1 + 9 = 8
- -2 + 9 = 7
- -3 + 9 = 6
All of these are correct options, basically, we want to have the same value in the left than in the right side.
For the final question:
- If both numbers are positive, the sign of the outcome is positive.
- If both numbers are negative, the sign of the outcome is negative.
- If the numbers have different signs, the sign of the outcome is the same as the sign of the number that has the largest absolute value.
If you want to learn more about sums and differences, you can read:
https://brainly.com/question/10853762
