Question 1203500
-1 * -2 = 2
2 * -2 = -4
-4 * -2 = 8
8 * -2 = -16
looks like you have a common multiplier of -2.
a formula would be y = -1 * (-2)^n, i believe.
when n = 0, y = -1
when n = 1, y = -1 * -2 = 2
when n = 3, y = -1 * (-2)^2 = -1 * 4 = 4
when n = 4, y = -1 * (-2)^3 = -1 * -8 = 8
when n = 5, y = -2 * (-2)^4 = -1 * 16 = -16.
etc.....