## anonymous 5 years ago How the heck do I write a set builder and interval out of 6-8(y+3)+5y>(2y-5)+13? once I worked it out I got y<-6m whats my next step?

1. anonymous

2. anonymous

thats a typo, I'm sorry.

3. anonymous

y<-6

4. anonymous

$let s = \left\{ y: y<-6 \right\}$

5. anonymous

in set builder, then the interval $y \in \left( -6, -\infty \right)$

6. anonymous

so how do I know where to put the infinity sign?

7. anonymous

oh wait i miss typed that, the -6 and - infinity shud be swapped. sorry

8. anonymous

the smaller value should always be on the left by convention since the interval starts at the left hand value and goes up to the right hand value

9. anonymous

so when do I use that squiggly line, and bracets instead of perenthisis?

10. anonymous

round brackets mean the endpoints arent in the interval and square brackets mean they are included

11. anonymous

so whats the interval to this specific one? $\xi x-6$

12. anonymous

im not sure i understand your notation, what does the lowercase delta stand for?

13. anonymous

Our professor was asking for some squiggly line for example: 8-6(x-3)>-4x+12 Solution: x<7 Set Builder Notation:$\xi x-1+<7\xi$ Interval Notation: (-$\infty , 5/2]$

14. anonymous

I'm sorry the interval notation is actually 7 not 5/2, but do you see what I mean?

15. anonymous

maybe its just the name he is using but in any book i have ever seen set builder means { } and u state the conditions for membership of the set in the brackets

16. anonymous

yes, maybe it is {

17. anonymous

so to graph y<-6 it would be <_______O I I I I I I I I I I -6