Semicolon Math Round 2
Note 's' means solved and 'u' means unsolved.
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Problem 1: Integer roots
Problem status: not solved
Value (if solved during a running contest): 70
Problem 2: Distance between centroids
Problem status: not solved
Value (if solved during a running contest): 150
Let \(ABCD\) be a square with side length \(1\). Let \(E\) be a point on side \(BC\) such that \(BE = EC\). Similarly, let \(F\) and \(G\) be points on side \(CD\) such that \(DF = FG = GC\). Let the intersection of \(AF\) and \(DE\) be \(H\) and the intersection of \(AG\) and \(DE\) be \(I\).
Define \(G_1\) to be the centroid of \(\triangle ADH\) and \(G_2\) to be the centroid of \(\triangle AHI.\) If \(G_1G_2\) can be written in form \(\frac{\sqrt{a}}{b}\) where \(a\) is a positive integer not divisible by the square of any prime and \(b\) is a positive integer, find \(a + b\).
Problem 3: Parabolas, lines, and circles
Problem status: not solved
Value (if solved during a running contest): 200
Let \(A\) and \(B\) be the points of intersection between the line \(x+y=-1\) and the circle with radius \(5\) centered at \((0,0).\) Let \(f(x) = ax^2+bx+c,\) where \(a, b, c\) are real numbers with \(a > 0\) pass through \(A\) and \(B.\) Additionally, let the minimum value of \(f(x)\) be located at \(C\) and the \(x\)-coordinate of \(C\) be \(1.\)
Let \(k\) be the sum of roots of \(f(x)\) and let \(D\) and \(E\) be the intersection between the line \(x+y=k\) and the circle with radius \(5\) centered at \((0,0).\) The value \(CD^2 + CE^2\) can be expressed as \(\frac{m}{n}\) where \(\gcd(m,n)=1\). Find \(m+n.\)