## Practice 3 - Visualizing Algebra

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Did you get the closed interval from negative 1 to 1? If so, you should be very
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proud of yourself. I know I am. Let's see how we got that solution. Remember
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when you're working with a compound inequality that's written in this form, we
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can perform operations as long as we do the same operation, to all three
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portions of the quation. The first thing I want to do is to get rid of this
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fraction by multiplying through by the least common denominator, and the least
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common denominator is 2. When I multiply 2 by negative 3, I get negative 6. When
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I multiply 2 by 5 x minus 1 over 2, I'm simply left with 5 x minus 1, and when I
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multiply 2 times 2, I get 4. Next I'm going to add 1 to each part of the
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equation so I can isolate the variable in the middle. When I do that, negative 6
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plus 1 is negative 5, and 4 plus 1 is positive 5. Now I can divide through by 5.
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Negative 5 divided by 5 is negative 1, less than or equal to x, less than or
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equal to 5 over 5 is positive 1. Let's draw that on the number line. This
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portion of the inequality says that negative 1 is less than or equal to x, which
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is the same as x is greater than or equal to negative 1. So, that means we're
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going to be going in that direction.
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This portion of the equation says x is less than or equal to positive 1, so we
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use a square bracket and the answer's going here. So we have the interval from
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negative 1 to 1 using the square brackets.
Title:
Practice 3 - Visualizing Algebra
Video Language:
English
Team:
Udacity
Project:
MA006 - Visualizing Algebra
Duration:
01:27
 Udacity Robot edited English subtitles for Practice 3 - Visualizing Algebra Cogi-Admin added a translation

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