1d (-5,0) is correct.
2c
3d
4e x may be at most -1 or at least 1.
5a
6c
7e all real numbers except the square root of 2 and - the square root of 2.
8e $233.33
9c
10e it should be x is greater than or equal to 1 of x=-1.
11d
12a
13a
14c
15c
16d
17a
18d
19d
20b
21a
22e it should be 3/7
23 y=x/2
24 80/9
25 16.8%
26 173.71 years
27a parabola with vertex (3,4), intercepts (0,-5), (1,0), (5,0).
27b (-infinity,4]
27c (-infinity,3]
28 4/11 = 0.3636