Theory:

We can add two integers using a number line.
 
1. Add \(4\) and \(3\) using a number line.
 
Step 1: Draw a number line with positive and negative numbers.
 
Step 2: Move \(4\) units from the right of \(0\).
 
Step 3: Now, move \(3\) units from the right of \(4\).
 
Numberline_4.png
 
Step 4: The number reached is \(4 + 3 = 7\).
 
 
2. Add \((-5)\) and \(4\) using a number line.
 
Step 1: Draw a number line with positive and negative numbers.
 
Step 2: Move \(5\) units from the left of \(0\).
 
Step 3: Now, move \(4\) units from the right of \(-5\).
 
Numberline_5.png
 
Step 4: The number reached is \((-5) + 4 = -1\).
 
 
3. Add \((-5)\) and \((-5)\) using a number line.
 
Step 1: Draw a number line with positive and negative numbers.
 
Step 2: Move \((-5)\) units from the left of \(0\).
 
Step 3: Now, move \((-5)\) units from the left of \((-5)\).
 
Numberline_6.png
 
Step 4: The number reached is \((-5) + (-5) = -10\).