The vertex of this parabola is at (-1,-3). Which of the following could be its equation?
(-1, -3)
O A. X=-2(y+3)2-1
B. x=-2(y - 3)2 - 1
C. X=-2(y + 1)2-3
D. X = -2(y - 1)2-3

Period is the time it takes for one “cycle” to complete. in the parent sine function, period is 2*pi since sin(0) = 0, sin(pi/2) = 1, sin(pi) = 0, sin(3pi/2) = -1, and sin(2pi) = 0. at that point, the sequence repeats itself. i’m not sure if your graph is similar to the sine function since you didn’t provide a picture, but you can find the period by looking at a graph.