To solve the expression \(-4 + 7\) using a number line:
- Start at \(-4\).
- Move to the right because you are adding a positive number (7).
- Count 7 units to the right from \(-4\):
- From \(-4\) to \(-3\) is 1 unit.
- From \(-3\) to \(-2\) is 2 units.
- From \(-2\) to \(-1\) is 3 units.
- From \(-1\) to \(0\) is 4 units.
- From \(0\) to \(1\) is 5 units.
- From \(1\) to \(2\) is 6 units.
- From \(2\) to \(3\) is 7 units.
After moving 7 units to the right from \(-4\), you land on \(3\).
Therefore, the solution to \(-4 + 7\) is \(3\).
The correct answer is 3.