questions to look at (units 1-3)

so this was my test.. unit one lol i didnt know how to do the last two pages. ahh..........

 why did i have to divide them by two? i dont get it.

                               
                                               trouble with e and f  (ans - e = |x| < 1, f = x<1)

                
                                                          trouble with 4  ans, x = 2

19 and 25 (19 - (-infinity, 0) U (0, infinity) 25 - (-infinity, -5/3) U (5, infinity)



3c) -2 root (6x+1) = 14   , ans no solution

3e) |7x+12| < -5 , ans no solution

7c) |(x-3)/(x+5)| < 2   , ans {x| x > -7/3, or x < -13}

6d) | 2x + 5 | <(or = to) |5x + 12|  , ans [-1, 1]

6e) root (x+5)  + 5 = root (x)  , ans undefined

6g) root (x+4) + root (x-4) = 2 (times) root (x-1)  , ans x=5

8c) |3x+2| = 2x - 4  , ans undefined