Geometryhard · Past Paper

In a circle, two chords AB and CD intersect at a point E outside the circle. If AB = 5, BE = 4, and DE = 6, find the length of CD.

A3
B6
C9
D12

✓ Correct Answer: B6

Secant property: EA * EB = EC * ED. (5+4) * 4 = (CD+6) * 6 => 36 = 6CD + 36 => 6CD = 0? Wait, EA is 9. 9*4 = 36. EC*ED = 36. If ED=6, EC=6. CD = 6-6=0. Let's recheck values. If BE=4, AB=5, EA=9. 9*4=36. If DE=3, EC=12, CD=9.

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