Problem

2025 AIME I Problem 11

A piecewise linear function is defined by f(x) = \begin{cases} x & \text{if} ~ -1 \leq x < 1 \\ 2 - x & \text{if} ~ 1 \leq x < 3\end{cases} and f(x + 4) = f(x) for all real numbers x. The graph of f(x) has the sawtooth pattern depicted below.

[asy] import graph; size(300); Label f; f.p=fontsize(6); yaxis(-2,2,Ticks(f, 2.0)); xaxis(-6.5,6.5,Ticks(f, 2.0)); draw((-7,0)--(7,0), black+0.8bp); draw((0,-2.2)--(0,2.2), black+0.8bp); draw((-6,-0.1)--(-6,0.1), black); draw((-4,-0.1)--(-4,0.1), black); draw((-2,-0.1)--(-2,0.1), black); draw((0,-0.1)--(0,0.1), black); draw((2,-0.1)--(2,0.1), black); draw((4,-0.1)--(4,0.1), black); draw((6,-0.1)--(6,0.1), black); draw((-7,1)..(-5,-1), blue); draw((-5,-1)--(-3,1), blue); draw((-3,1)--(-1,-1), blue); draw((-1,-1)--(1,1), blue); draw((1,1)--(3,-1), blue); draw((3,-1)--(5,1), blue); draw((5,1)--(7,-1), blue); [/asy]

The parabola x = 34y^{2} intersects the graph of f(x) at finitely many points. The sum of the y-coordinates of all these intersection points can be expressed in the form \tfrac{a + b\sqrt{c}}{d}, where a, b, c, and d are positive integers such that a, b, d have greatest common divisor equal to 1, and c is not divisible by the square of any prime. Find a + b + c + d.

Leading zeroes must be inputted, so if your answer is 34, then input 034


Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.


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