Answer
Part 1: 3 + (-7) = -4
Part 2: Irrational numbers
Explanation
Part 1
A number line can be used to add and subtract integers. When adding positive numbers we move to the right and when adding negative numbers we move to the left.
When subtracting positive numbers we move to the left and when subtracting negative numbers we move to the right.
∴ From the number line shown above we are moving 7 steps to the left. this means we adding a (-7) to 3. This give the answer as (-4).
3 + (-7) = -4
Part 2
√7 = 2.645751311...
This number is not a whole number neither can it be written as a ratio. That is it can not be written in the form of a/b where b≠0. Such numbers are called irrational numbers.
