|(8x+56)/56|>/10 I got -77 and 63 for the answers but I don't know how to put it in interval notation
I tried every way and it says incorrect or i have overlapping intervals
Do you think that it is the right answer or do you need help solving
is the >10 or is it really >/10
its > with a line under it
Im 90 percent sure that is the right answer
let me check the work first okay
okay
did you end up getting [-77,63]
yea
did you have answer chocies
what do you mean?
like is it multiple choice
no
hmm sorry i am of no help but the only choice i would think it would be was [63,infinity). sorry
its okay thanks
Hey ms britt c:
Hi again!
\[\Large\rm \left|\frac{8x+56}{56}\right|\ge 10\]Multiply both sides by 56,\[\Large\rm \left|8x+56\right|\ge 560\]Then we end up with our two cases again when we drop the absolute bars.\[\Large\rm \cases{8x+56\ge560\\ \rm 8x+56\le-560}\]Solving for x in each case gives us:\[\Large\rm \cases{x\ge63\\ \rm x\le-77}\]So it looks like you've got the correct numbers. Just need some help writing in this in interval notation?
Do you understand why the inequality flipped directions in the second case?
yes
dividing by a negative
x greater than or equal to 63, So we'll have 63 and all the values larger than that heading towards positive infinity. x less than or equal to -77, We'll also have -77 and all the values smaller than that, heading towards negative infinity.
Note: ALWAYS use a round bracket for \(\Large\rm \infty\). We don't "include" infinity in our interval since it doesn't represent an actual value. So for our lower side we'll have: \(\Large\rm (\infty,~ -77 \) What is different in this problem? What type of bracket do we want on the -77?
]
Good good, I just realized I made a typo, lemme fix the -infty,\[\Large\rm (-\infty,~ -77]\]So that's one of our pieces.
How bout the other one, what do you think? c:
(inf, 63]
wait [63, inf)
Yah there we go! We want the SMALLER number on the left since we read from left to right.\[\Large\rm [63,\infty)\]
How do we put them together? Union or Intersection? Here, I'll give you a little cheat sheet.
|dw:1412304105890:dw|
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