SOLUTION: how do you solve a ____ >0? by using interval notation and graphing it?

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Question 248916: how do you solve


a
____ >0? by using interval notation and graphing it?
a+2

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve
a
____ > 0? by using interval notation and graphing it?
a+2
---------------------
1st: Notice that a cannot be -2 because of the denominator.
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2nd: Solve the EQUALITY which is the boundary for the INEQUALITY.
a/(a+2) = 0
Solution: a = 0
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3rd: Draw a number line and plot a = -2 and a = 0
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4th: Pick a check point from each of the three number line intervals
to see where the solutions for the INEQUALITY lie.
Test the check point values in a/(a+2) > 0
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If a = -3 you get: -3/(-1) > 0 ; true, so solutions in (-inf,-2)
If a = -1 you get: -1/(1) > 0 ; false, so no solutions in (-2,0)
If a = 1 you get: 1/(3) > 0 ; true, so solutions in (0,+inf)
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Final answer: (-inf,-2)U(0,+inf)
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Cheers,
stan H.