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Given an ABCD inscribed quadrilateral, where the AB side is the diagonal of the circum- circle of the quadrilateral. BC = 3cm, CD = 5 cm and BCDZ = 120°. Give the length of the BD diagonal, AB and AD sides and the other angles.​

User Alexander Vasilyev
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Answer:

Explanation:

Given an ABCD inscribed quadrilateral, where the AB side is the diagonal of the circum-circle of the quadrilateral, we can calculate various properties by using basic trigonometry. Firstly, let us determine the length of BD. Since BCDZ = 120° and BC = 3cm ,we can use Sine rule to find out BD which will be equal to 4 cm. Secondly, we need to find AB and AD sides lengths as well as other angles in order for our calculations to be complete. To do this we will use Cosine rule since all three sides are known: BC=3cm; CD=5cm;BD=4 cm . This gives us a value for angle CBD which is approximately 39° and consequently angle BAD is also 39° since they add up together (BAD+CBD)to 180 degrees due their being opposite each other on a straight line..Finally ,using cosine again with these new values gives us both AB(6)and AD(2).

To summarise : Lengths -AB: 6 cm ; BD : 4 cm ;AD 2CM Angles - BCDZ :120 ° ; CBD & BAD :39 °

In conclusion , given an ABCD inscribed quadrilateral whose one side was already identified as its circumference diameter it was possible through simple trigonometric equations such s Sines Rule or Cosines Rule determine its remaining lengths ans angles accurately .

User DavidOhara
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