Graphing Compound Inequalities
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Otis
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Hello Hal. That needs to say 'or'.
c < -5 is correct, but -c < -7 is not finished, yet. Instead of stating what -c is, you need to state what c is (i.e., multiply each side by -1 and follow the rule regarding multiplication of an inequality by a negative number).
Please see the worked examples and videos about graphing compound inequalities on this page.
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pka
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HallsofIvy
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From -c< -7 we have c> 7. Since that has just a single variable, we graph it on a number line. Locate the point "7" on your number line and indicate the numbers larger than that. How you do that really depends upon what your teacher wants. One common way would be the draw a small "open" circle at 7 (not shaded) to indicate that 7 is not included and an arrow on the interval above 7 pointing upward to indicate "larger than 7". Another way is to draw a "parenthesis" at 7, "opening" to the right. Similarly indicate "c< -5" mark the numbers on the number line below -5.
Notice that those intervals do not overlap. There are NO numbers that satisfy both "9- c< 2" and "-3c< 15". The two intervals show those numbers that satisfy "9- c< 2" or "-3c< 15".
Notice that those intervals do not overlap. There are NO numbers that satisfy both "9- c< 2" and "-3c< 15". The two intervals show those numbers that satisfy "9- c< 2" or "-3c< 15".
Steven G
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You have to understand the difference between AND and OR.
If I say that I will study math and history tonight what must I study for my statement to be true? Since this is an AND statement I must study both math and history
If I say that I will study math or history tonight what must I study for my statement to be true? Since this an OR statement then I must study only math or only history or both math and history.
With an AND statement with two inequalities both inequalities must be drawn separately and the final result will be wherever the intersection is.
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