(a) Dilation is the process of extending the line segment AB to the longer one A'B'. The scale factor has to be larger than 1, and also it has to be positive.
(b) To get the dilation factor, you should first compute the length of AB, then compare it to the length of A'B'.
A is the point (-4, 2), and B is the point (2, -4). So the length of AB is
√((-4 - 2)² + (2 - (-4))²) = √((-6)² + 6²) = √72
A' is the point (-8, 4) and B' is (4, -8). The coordinates of A' and B' are twice the coordinates of A and B, so the distance is
√((2(-4) - 2(2))² + (2(2) - 2(-4))²) = √(2²×72) = 2√72
Then the dilation factor is
(2√72) / √72 = 2
As for dying, don't worry about it. It happens to everyone.