The Subtraction Property of Inequality is shown below.
Words
Let a, b, and c be real numbers.
If
If
This property is also true for
Examples
Diagram
The diagram below illustrates one way to think about this rule.
What are the solutions of
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Subtract 6 from each side. |
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Simplify. |
The solutions of
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How is this inequality different from others you have seen before?
The expression t + 6 involves addition, so you have to use subtraction to undo the addition and isolate the variable.
✓ Got It?
Computers The hard drive on your computer has a capacity of 120 gigabytes (GB). You have used 85 GB. You want to save some home videos to your hard drive. What are the possible sizes of the home video collection you can save?
Relate |
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Define | Let
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Write |
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How do you know which inequality symbol to use?
Words and phrases like at most, no more than, and maximum may indicate that you should use
The home video collection can be any size less than or equal to 35 GB.