In \( \Large \triangle ABC \), D and E are points on sides AB and AC, such that \( \Large DE \parallel BC \). If AD = x, DB = x - 2, AE = x + 2 and EC = x - 1, then the value of x is


A) 4

B) 2

C) 1

D) 8

Correct Answer:
A) 4

Description for Correct answer:

\( \Large \because DE \parallel BC \)

\( \Large \therefore \frac{AD}{DB} = \frac{AE}{EC} \)



=> \( \Large \frac{x}{x-2} = \frac{x+2}{x-1} \)

=> \( \Large x^{2} - x = x^{2} - 4 \)

=> x = 4


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