The figure below shows two sectors in which AB and CD are arcs of concentric circles centre O. Angle AOB = 2/5 radians and AD =...

The figure below shows two sectors in which AB and CD are arcs of concentric circles centre O.
Angle AOB = 2/5 radians and AD = BC = 5 cm.

Given that the perimeter of the shape ABCD is 24 cm, calculate the length of OA.

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Length of an arc = ?^cr
Let OA = x
2/5x + 2/5 (x + 5) = 14
2x + 2x + 10 = 70
4x = 60
x = 15
? OA= 15 cm

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Kavungya answered the question on November 13, 2019 at 10:56

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