pre-calculus - checking if i did it right

[watchthesky30]

i just want to know if i got the right answer for these questions. thanks! If i didn't do it right, please let me know. I want to learn how to do it before an exam. Thanks

1) (2/5 + 1/2) ÷ (1/10 + 3/15)
i got the answer 3/5. not sure if i did it right.

2) i have to express x?-5 in interval notation
and i got [-5, infinity)

3) i have to evaluate this |? 5 -5|
i got 5 - ?5

4) i have to evaluate this |10 - ?|
i got ? - 10

5) A = {x|x?-2}
B = [x|x< 4}
C = {x|-1<x? 5}
i have to find A ? C
i got {x|x? -2}

and i have to find A ? B
i got {x|-2?x<4}

 

[tkhunny]

1) Show us how you would get an answer for which you are sure.

2) Good.

3) Good.

4) Whoops. Try again.

5a) So, you're saying that x = -2 is in the intersection? Think about C and that conclusion.

5b) Right.

Kind of a mixed bag. If I were to guess, I would guess that you were distracted while you were doing this assignment. Did you turn off the TV? Maybe you were watching the sky and contemplating the cosmos? Focus and try them over.