Given an angle and length, how do I calculate the coordinates

Question

Assuming the upper left corner is (0,0) and I\'m given an angle of 30 degrees, a starting point of (0,300), a line length of 600, how do I calculate the ending point of the

Answer 1

// edit to add conversion
    #define radian2degree(a) (a * 57.295779513082)
    #define degree2radian(a) (a * 0.017453292519)

        x = start_x + len * cos(angle);
        y = start_y + len * sin(angle);