Help with an absolute value inequality problem! xxxxxxxxx
one problem...
do you know what kinds of numbers | .. | will output?
No...I don't think I understand what you mean
|...| is absolute value of some number
I'm asking you to tell me what kinds of numbers will result after absolute value is applied
Oh ok, no I don't know will output. How do I find that out?
|..| is the distance measurement of .. from 0... distance is either a positive or 0 number
|x+5| is positive or zero for any x
you have everything great up til \[|x+5|>\frac{-3}{7}\]
since |x+5| is always either positive or zero that means |x+5| is greater than any negative number
Oh okay! So I wouldn't do the or |x+5| < 3/7 part right?
plug in any x you will see |x+5| is always greater than -3/7
so then my answer would only be x > -38/7?
no your solution is all real numbers it doesn't matter what you input for x |x+5| is ALWAYS greater than -3/7 (no matter what x)
oh wait...so then if its always greater than -3/7 would that be all real numbers? sorry if i'm interrupting
Ok! got it thank you so much @freckles!!! Seriously the best
it didn't matter what negative number was on that other side absolute value of anything is always greater than any negative number since absolute value of anything always outputs positive number or zero
another problem just for fun: if you had |x+5|<-3/7 there would be no solution
one last question though...so I checked on mathway and it says the answer would be (3, infinity)... why is that? I don't know how it could be 3.
can't tell you why mathway would say that mathway if it really said said that when you typed in 7|x+5|+6>3 is incorrect
Ok, that's what i thought too! Thanks for your help again freckles :)
http://www.wolframalpha.com/input/?i=7%7Cx%2B5%7C%2B6%3E3 the result true means it is is a true inequality for all x
Thanks for that! Appreciate it
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