static double adjacentLength(Vector2d hypotenuse, Vector2d adjacent, double oppositeLength) {
        return Math.tan(hypotenuse.angle(adjacent)) * oppositeLength;
    }
static double adjacentLength ( Vector2d hypotenuse , Vector2d adjacent , double oppositeLength ) { return Math . tan ( hypotenuse . angle ( adjacent ) ) * oppositeLength ; }
Given vectors for the hypotenuse and adjacent side of a right angled
triangle and the length of the opposite side, determine how long the
adjacent side size.

@param hypotenuse vector for the hypotenuse
@param adjacent vector for the adjacent side
@param oppositeLength length of the opposite side of a triangle
@return length of the adjacent side