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We know how to graph things like: |
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| But what do we do with: | ||
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| What we need is a formula to use | ||
| to get rid of the absolute value lines. | ||
| Here it is ... | ||
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| The first formula is pretty easy to remember, | ||
| but it would be nice if there was a trick | ||
| to help us keep the other two straight. | ||
| -10 < X + 3 < 10 which has X in the middle, | ||
| takes up LESS space to write than the other one | ||
| so it goes with less than: (|x + 3|>10) | ||
| X + 3 > 10 or X + 3 < -10 which has two pieces, | ||
| takes up a GREATER amount of space than the other one | ||
| so it goes with greater than (|X + 3|>10) | ||
| And from there, you can find X. | ||
| Oh sure you can, | ||
| we did this kind of stuff two pages ago. | ||
| Example: | ||
| Solve for X and graph ... | ||
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| So: | ||
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| So the graph looks like this ... | ||
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| Example: | ||
| Solve for X and graph ... | ||
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| So: | ||
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| DID YOU SEE THE LESS THAN AND GREATER THAN SIGNS | ||
| CHANGE DIRECTION WHEN WE DIVIDED BY -5? | ||
| So: | ||
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| The graph of this is: | ||
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copyright 2005 Bruce Kirkpatrick |
