Why does the trajectory return a domain which appears to "rotate" around the origin point (0, 0)?

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I am trying to use the trajectory formula in a video game I am designing to calculate the parabola a fishing bobber follows as it fly's through the air.

The formula I am using is as follows: The formula I am using.

variable A refers to the angle in degrees.

variable X refers to the position on the X axis


What I've found is that when I supply a values such as 45 degrees I will get a parabola that essentially starts at 0,0 and ends on a positive X value. While a value such as 15 will travel in the opposite direction.

How do I make it so all of the returned parabola's start at X = 0 and end at a positive X value?

Also why does the formula work in the way I've laid out?

Examples:

When A = 45 degrees A = 45 degrees

When A = 15 degrees A = 15 degrees