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2022 MBMT Geometry Round - Montgomery Blair Math Tournament

Source:

October 14, 2023
MBMTgeometry

Problem Statement

[hide=D stands for Dedekind, Z stands for Zermelo]they had two problem sets under those two names
D1. A Giant Hopper is 200200 meters away from you. It can hop 5050 meters. How many hops would it take for it to reach you?
D2. A rope of length 66 is used to form the edges of an equilateral triangle (a triangle with equal side lengths). What is the length of one of these edges?
D3 / Z1. Point EE is on side ABAB of rectangle ABCDABCD. Find the area of triangle ECDECD divided by the area of rectangle ABCDABCD.
D4 / Z2. Garb and Grunt have two rectangular pastures of area 3030. Garb notices that his has a side length of 33, while Grunt’s has a side length of 55. What’s the positive difference between the perimeters of their pastures?
D5. Let points AA and BB be on a circle with radius 66 and center OO. If AOB=90o\angle AOB = 90^o, find the area of triangle AOBAOB.
D6 / Z3. A scalene triangle (the 33 side lengths are all different) has integer angle measures (in degrees). What is the largest possible difference between two angles in the triangle?
D7. Square ABCDABCD has side length 66. If triangle ABEABE has area 99, find the sum of all possible values of the distance from EE to line CDCD.
D8 / Z4. Let point EE be on side AB\overline{AB} of square ABCDABCD with side length 22. Given DE=BC+BEDE = BC+BE, find BEBE.
Z5. The two diagonals of rectangle ABCDABCD meet at point EE. If AEB=2BEC\angle AEB = 2\angle BEC, and BC=1BC = 1, find the area of rectangle ABCDABCD.
Z6. In ABC\vartriangle ABC, let DD be the foot of the altitude from AA to BCBC. Additionally, let XX be the intersection of the angle bisector of ACB\angle ACB and ADAD. If BD=AC=2AX=6BD = AC = 2AX = 6, find the area of ABCABC.
Z7. Let ABC\vartriangle ABC have ABC=40o\angle ABC = 40^o. Let DD and EE be on AB\overline{AB} and AC\overline{AC} respectively such that DE is parallel to BC\overline{BC}, and the circle passing through points DD, EE, and CC is tangent to AB\overline{AB}. If the center of the circle is OO, find DOE\angle DOE.
Z8. Consider ABC\vartriangle ABC with AB=3AB = 3, BC=4BC = 4, and AC=5AC = 5. Let DD be a point of ACAC other than AA for which BD=3BD = 3, and EE be a point on BCBC such that BDE=90o\angle BDE = 90^o. Find ECEC.
PS. You should use hide for answers. Collected [url=https://artofproblemsolving.com/community/c5h2760506p24143309]here.