# Geometry

 1. (13 p.) Let $$ABC$$ be a triangle with sides 3, 4, 5 and $$DEFG$$ a $$6 \times 7$$ rectangle. A line divides $$\triangle ABC$$ into a triangle $$T_1$$ and a trapezoid $$R_1$$. Another line divides the rectangle $$DEFG$$ into a triangle $$T_2$$ and a trapezoid $$R_2$$, in such a way $$T_1\sim T_2$$ and $$R_1\sim R_2$$. The smallest possible value for the area of $$T_1$$ can be expressed as $$p/q$$ for two relatively prime positive integers $$p$$ and $$q$$. Evaluate $$p+q$$.

 2. (10 p.) Given a rhombus $$ABCD$$, the circumradii of the triangles $$ABD$$ and $$ACD$$ are 12.5 and 25. Find the area of $$ABCD$$.

 3. (6 p.) A right circular cylinder has a diameter 12. Two plane cut the cylinder, the first perpendicular to the axis and the second at a $$45^o$$ angle to the first, so that the line of intersection of the two planes touches the cylinder at a single point. The two cuts remove a wedge from the cylinder. If $$V$$ is the volume of the wedge calculate $$V/\pi$$.

 4. (22 p.) Let $$K$$ and $$L$$ be the points on the sides $$AB$$ and $$BC$$ of an equilateral triangle $$ABC$$ such that $$AK=5$$ and $$CL=2$$. If $$M$$ is the point on $$AC$$ such that $$\angle KML=60^o$$, and if the area of the triangle $$KML$$ is equal to $$14\sqrt3$$ then the side of the triangle $$ABC$$ can assume two values $$\frac{a\pm \sqrt b}c$$ for some natural numbers $$a$$, $$b$$, and $$c$$. If $$b$$ is not divisible by a perfect square other than 1, find the value of $$b$$.

 5. (46 p.) Let $$\triangle ABC$$ have $$AB=6$$, $$BC=7$$, and $$CA=8$$, and denote by $$\omega$$ its circumcircle. Let $$N$$ be a point on $$\omega$$ such that $$AN$$ is a diameter of $$\omega$$. Furthermore, let the tangent to $$\omega$$ at $$A$$ intersect $$BC$$ at $$T$$, and let the second intersection point of $$NT$$ with $$\omega$$ be $$X$$. The length of $$\overline{AX}$$ can be written in the form $$\tfrac m{\sqrt n}$$ for positive integers $$m$$ and $$n$$, where $$n$$ is not divisible by the square of any prime. Find $$m+n$$.

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