8.5. Through the point with coordinates $(2,2)$, lines (including two parallel to the coordinate axes) are drawn, dividing the plane into angles of $18^{\circ}$. Find the sum of the abscissas of the points of intersection of these lines with the line $y=2016-x$.
Answer: 10080. Solution. The picture is symmetric with respect to the line $y=x$, so the sum of the abscissas is equal to the sum of the ordinates. Through the point $(2,2)$, 10 lines are drawn, and the line $y=2016-x$ intersects all of them. For each point on the line $y=2016-x$, the sum of the coordinates is 2016, so the total sum of the abscissas and ordinates is 20160, and the sum of the abscissas is half of that.

Criterion. 2 points for the correct answer without a correct justification. 5 points if all ideas are found, but the answer is incorrect due to a wrong count of the number of intersection points (for example, the student counts 9 or 18 points).