1. Two bisector BD and CE of the triangle ABC intersect at O. Suppose that BD.CE = 2BO.OC . Denote by H the point in BC such that .\(OH⊥BC\) . Prove that AB.AC = 2HB.HC
2. Given a trapezoid ABCD with the based edges BC=3cm , DA=6cm ( AD//BC ). Then the length of the line EF ( \(E\in AB,F\in CD\) and EF // AD ) through the intersection point M of AC and BD is ............... ?
3. Let ABC be an equilateral triangle and a point M inside the triangle such that \(MA^2=MB^2+MC^2\) . Draw an equilateral triangle ACD where \(D\ne B\) . Let the point N inside \(\Delta ACD\) such that AMN is an equilateral triangle. Determine \(\widehat{BMC}\) ?
4. Given an isosceles triangle ABC at A. Draw ray Cx being perpendicular to CA, BE perpendicular to Cx \(\left(E\in Cx\right)\) . Let M be the midpoint of BE, and D be the intersection point of AM and Cx. Prove that \(BD⊥BC\)
Given a square with the length of one side is 8 cm and a isosceles triangle with the length of its base is 12 cm. If the area of the square is equal to the area of the isosceles triangle then what is the length of the height of the isosceles triangle, in cm?
Given that ABCD is a rectangle with AB = 12 cm, AD = 6 cm. M and N are respectively midpoint of segments BC and CD. Find the area of triangle AMN in square centimeters.
Given the right triangle ABC (A^ = 90o), BD is the bisector of the angle at B ( D of AC ). If AD = 6cm and AB = 12cm then the area of the right triangle ABC is ...... cm2.
Given the right triangle ABC (A^ = 90o), BD is the bisector of the angle at B ( D of AC ). If AD = 6cm and AB = 12cm then the area of the right triangle ABC is ...... cm2.
Given the right triangle ABC (A^ = 90o), BD is the bisector of the angle at B ( D of AC ). If AD = 6cm and AB = 12cm then the area of the right triangle ABC is ...... cm2.
In triangle ABC, BC=AC and BCA=900. D and E are points on AC and AB respectively such that AD=AE and 2CD =BE.Let P be the point of intersection of BD with the bisector of angle CAB. What is the angle PCB in degrees?
Let P be the intersection point of 3 internal bisectrices of a given triangle ABC. The line passing through P and perpendicular to CP intersects AC and BC at M and N. If AP=3cm, BP=4cm, compute AM/BN?
Given acute triangle ABC(AB<AC). O is the midpoint of BC, BM and CN are the altitudes of triangle ABC. The bisectors of angle \(\widehat{BAC}\)and \(\widehat{MON}\)meet each other at D. AD intesects BC at E. Prove that quadrilateral BNDE is inscribed in a circle.s
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