D and E are points on the sides AB and AC respectively of a ΔABC such that DE || BC.

Find the value of x, when



AD = 4 cm, DB = (x - 4) cm, AE = 8 cm and EC = (3x -19) cm.

Given: AD = 4 cm, DB = (x – 4) cm, AE = 8 cm and EC = (3x – 19) cm

By Thale’s theorem,




4(3x – 19) = 8(x – 4)


12x – 76 = 8x – 32


12x – 8x = 76 – 32


4x = 44


x = 44/4 = 11


Thus, x = 11 cm


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