Three consecutive sides of a quadrilateral circumscribed about a circle are related as 2: 5: 7

Three consecutive sides of a quadrilateral circumscribed about a circle are related as 2: 5: 7, the perimeter of a quadrilateral is 54 cm, find its sides

Let side BC = 2 * X, then CD = 5 * X, and side AD = 7 * X.

Since a circle is inscribed in a quadrilateral, the sums of its opposite sides are equal.

AB + CD = BC + AD.

AB + 5 * X = 2 * X + 7 * X.

AB = 9 * X – 5 * X = 4 * X.

Knowing the perimeter of the quadrilateral, we define X.

2 * X + 4 * X + 5 * X + 7 * X = 54.

18 * X = 54.

X = 54/18 = 3.

Then the side AD = 7 * 3 = 21 cm,

CD = 5 * 3 = 15 cm,

BC = 2 * 3 = 6 cm,

AB = 4 * 3 = 12 cm.

Answer: The sides of the quadrangle are 6 cm, 12 cm, 15 cm, 21 cm.



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