## marcelie one year ago Help me !!!! For the following exercises solve the equation below and express the answer using set notation. l 6-x l = 5 But the answer is 1, 1/2 , -2. How did they get these answers ?

1. marcelie

This is what i did : l 6-x l = 5 -x +6 = 5 x = 1 ? please tell me if i am correct or wrong ?

2. anonymous

you are correct

3. imqwerty

yea x=1 or x=11 are the answers :) u are 100% correct :D

4. zzr0ck3r

I would not say you are 100% correct. You are 50% correct. Remember $$|A|=b$$ means $$a=b$$ and $$-a=b$$ So you have $$6-x=5$$ which gives $$x=1$$ But we must also consider $-(6-x)=5$ which leads to $$x=11$$.

5. anonymous

yes

6. zzr0ck3r

But we are all actually wrong as it asked for the answer in set notation, so the answer is $$\{1,11\}$$

7. marcelie

so the interval notation is from smallest to biggest ?

8. imqwerty

$\left\{ 1,11 \right\}$means that there r 2 elementary solutions 1 and 11 :)

9. anonymous

when ever you see the modulus you have to consider the negative and positive values means less then the positive value and greater than the negative value like that $\left| x \right|=4$ it means -4<x>4

10. marcelie

oh okay . Got it !! Thank Yous !!! I have another equation bur under same category. l 4x-2 l =11 x= 13/4 and x = -9/4 ? interval notation : { -9/4 , 13/4 }

11. anonymous

You are correct

12. marcelie

for my second problem ?

13. anonymous

yes! :) now you got the concept buddy

14. anonymous

now close this question and ask new :)

15. marcelie

Okay. I checked my solution book and it did include the - 9/4 ?

16. marcelie

i mean 9/4 .

17. anonymous

wait in book -9/4 is not given ?

18. marcelie

yes , the interval notation says { 9/4 , 13/4}

19. anonymous

no it will be -9/4 to 13/4 not 9/4

20. marcelie

Okay . Thanks.

21. anonymous

np