Question 10970
Your daughter's math book should have a section on "Real numbers" and their classification. 

Natural numbers:  Also called "the counting numbers"  This set of numbers includes: 1, 2, 3, 4, 5, ....  In other words, all of the positive numbers, not including zero.

Whole numbers: This set of numbers consists of the natural numbers above plus zero. 0, 1, 2, 3, 4, 5, ...

Integers:  To the above set of numbers, we now add the negative (whole) numbers.  So this set includes"...-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5...

Rational numbers: This set of numbers includes all of those number that can be written as a fraction of one integer over another, with one exception! The denominator cannot be zero.

Using the above description of integers, a win by seven points would be expressed as +7.

And an elevation of 3,400 ft. would be expressed as +3,400 ft.

On the other hand, a loss of ten points would be expressed as -10.

In these kinds of problems, there are certain words that indicate a negative quantity and certain words that indicate a positive quantity.  Here are some examples:

Positive:
Gain, Win, More, Bonus, Increase, Additional...you can probably think of more.

Negative: 
Loss, Lose, Less, Decrease, Below, Lower, Under, Depth...

I hope this helps.