Question

Можно ли разбить четырехугольник А,B,C,D на два треугольника каждый из которых имеет прямой угол ? на два треугольника не имеющих прямые углы ?

Answer 1

Если четырех угольник прямоугольный то можно,а если не прямоугольный то нельзя

Answer 2

Can a Quadrilateral ABCD be Divided into Two Triangles, Each with a Right Angle?

Yes, a quadrilateral ABCD can be divided into two triangles, each with a right angle. This can be achieved by drawing one of the diagonals of the quadrilateral. When a diagonal is drawn, it divides the quadrilateral into two triangles. One of these triangles will have a right angle if the quadrilateral is cyclic, meaning its vertices lie on the circumference of a circle.

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Can a Quadrilateral ABCD be Divided into Two Triangles, Neither of Which Have Right Angles?

Yes, a quadrilateral ABCD can be divided into two triangles, neither of which have right angles. This can be achieved by drawing a diagonal that does not form a right-angled triangle. In a non-cyclic quadrilateral, it is possible to draw a diagonal that does not form a right-angled triangle when the quadrilateral is divided.

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