+42 -55

-13

To add +42 and -55, follow these steps:

Step 1: Write down the numbers vertically with the plus sign in front of the positive number and the minus sign in front of the negative number:

+42
-55

Step 2: Align the numbers vertically by place value (units, tens, hundreds, etc.):

+42
-55

Step 3: Start from the rightmost column (units column) and add the numbers:

+42
-55
-----
-13

Step 4: Write the result below the line:

+42
-55
-----
-13

So, +42 minus 55 equals -13.