The length of DE is 3 units.
What is arc?
The part or segment of the circumference of a circle.
A straight line that could be drawn by connecting the two ends of the arc is known as a chord of a circle. If the length of an arc is exactly half of the circle, it is known as a semicircular arc.
What is theorem of similarity?
If two triangles are similar, then the ratio of the area of both triangles is proportional to the square of the ratio of their corresponding sides.
Given:
∠A = ∠E (same arc BD)
ΔXDA ~ ΔXBE
Now, the ratio of the corresponding side
XE / XA = XB / XD
As, XE = (3 + DE)
(3 + DE) / 9 = 2 / 3
9 + 3DE = 18
3DE = 9
DE = 3 units
Learn more about this arc here:
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