### Using a Formula to Subtract Numbers in Google Spreadsheets

In order to subtract two or more numbers in Google Spreadsheets, you need to create a formula.

Important points to remember about Google Spreadsheet formulas:

- Formulas in Google Spreadsheets always begin with the equal sign (
**=**) - The equal sign is always typed into the cell where you want the answer to appear
- The subtraction sign in Google Spreadsheets is the dash ( - )
- The formula is completed by pressing the Enter key on the keyboard or by moving the cell highlight to another cell with the mouse or arrow keys on the keyboard.

### Seeing the Answer, Not the Formula

Once entered into a worksheet cell, the answer or results of the formula are displayed in the cell rather than the formula itself.

In the case of the example above, the answer **10** would appear in the cell where the formula was entered rather than the formula.

### Seeing the Formula, Not the Answer

There are two easy ways to view the formula after it has been entered:

- click once with the mouse pointer on the cell containing the answer - the formula is displayed in the formula bar above the worksheet.
- double click on the cell containing the formula - this places the program in
*edit mode*and allows you to see and change the formula in the cell itself.

### Improving the Basic Formula

Even though entering numbers directly into a formula, such as **= 20 - 10** works, it is not the best way to create formulas.

The best way is to:

- enter the numbers to be subtracted into separate worksheet cells;
- enter the cell references for those cells containing the data into the subtraction formula.

### Using Cell References in Formulas

Google Spreadsheets has thousands of cells in a single worksheet. To keep track of them all each one has an address or reference that is used to identify the location of the cell in a worksheet.

These cell references are a combination of the vertical column letter and the horizontal row number with the column letter always written first - such as A1, D65, or Z987.

These cell references can also be used to identify the location of the data used in a formula. The program reads the cell references and then plugs in the data in those cells into the appropriate place in the formula.

In addition, updating the data in a cell referenced in a formula results in the formula answer automatically being updated as well.

### Pointing at the Data

In addition to typing, using point and click (clicking with the mouse pointer) on the cells containing the data can be used to enter the cell references used in formulas.

Point and click has the advantage of reducing errors caused by typing errors when entering cell references.

### Example: Subtract Two Numbers Using a Formula

The steps below cover how to create the subtraction formula located in cell C3 in the image above.

### Entering the Formula

To subtract 10 from 20 and have the answer appear in cell C3:

- Click on cell C3 with the mouse pointer to make it the active cell;
- Type the equal sign (
**=**) in cell C3; - Click on cell A3 with the mouse pointer to add that cell reference to the formula after the equal sign;
- Type a minus sign (
**-**) following the cell reference A1; - Click on cell B3 with the mouse pointer to add that cell reference to the formula after the minus sign;
- Press the Enter key on the keyboard
- The answer 10 should be present in cell C3
- To see the formula, click on cell C3 again, the formula is displayed in the formula bar above the worksheet

### Changing the Formula Results

- To test the value of using cell references in a formula, change the number in cell B3 from 10 to 5 and press the Enter key on the keyboard.
- The answer in cell C3 should automatically update to 15 to reflect the change in data.

### Expanding the Formula

To expand the formula to include additional operations - such as addition, multiplication, or more division shown in rows four and five in the example - just continue to add the correct mathematical operator followed by the cell reference containing the data.

### Google Spreadsheets Order of Operations

Before mixing different mathematical operations, be sure you understand the order of operations that Google Spreadsheets follows when evaluating a formula.