Which statement about the value of x is true?

x > 38

In this case, x is a exterior angle of the triangle. The exterior angle of a triangle is the sum of the nonadjacent interior angles of the triangle.

Therefore:
x = 38 + 39
x = 77

77 > 38
x > 38

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.