SOLUTION: Sec 8.1 #18 Title Solutions of compound inequalities, Determine whether -4 satisfies each compound inequality -3x > 0 and 3x-4 < 11

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Question 134327: Sec 8.1 #18
Title Solutions of compound inequalities,
Determine whether -4 satisfies each compound inequality
-3x > 0 and 3x-4 < 11
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-3x+%3E+0 Start with the first inequality


-3%28-4%29+%3E+0 Plug in x=-4


12+%3E+0 Multiply


Since this inequality is true, x=-4 works for the first inequality.


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3x-4+%3C+11 Start with the first inequality


3%28-4%29-4+%3C+11 Plug in x=-4


-12-4+%3C11 Multiply


-16+%3C11 Subtract

Since this inequality is true, x=-4 works for the second inequality.



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Conclusion:

Since x=-4 satisfies both inequalities, this means that x=-4 is in the solution interval.