What If Analysis

There are three features in Excel that can be used for what-if analysis.
Data Tables - 1 or 2 variables
Goal Seek - 1 or 2 variables
Scenario Manager - more than 2 variables
All three of these features can be accessed from the Data Tab

Scenario Manager

Can have a maximum of 32 different values
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Goal Seek

Goal Seek is useful when you know the answer you want from a formula, but you are not sure what value is needed to get that result.
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Data Tables

A data table can accommodate 1 or two variables
One variable for the row input.
One variable for the column input.
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