-40
-36
41
49 (it is an arithmetic series that adds 5 then 7 then 9 then 11 then 13)
3 ± 5.19615i (to 5 dp) where i is the imaginary sq root of -1equivalently, 3 ± sqrt(-27) = 3[1 ± sqrt(-3)]
4 and 9
164
It is: -6 and -6
21
-20
0
9
-40
-18 + -18 = -36 -18 x -18 = 324 The two numbers are both -18.
49
The factor pairs of 36 are (36, 1) (18, 2) (12, 3) (9, 4) (6, 6) None of them add up to 9. If that was -36, you could use 12 and -3
144