D and E are respectively the points on the sides AB and AC of a ΔABC such that AB = 5.6 cm. AD = 1.4 cm. AC = 7.2 cm and AE = 1.8 cm. Show that DE∥BC. [1 MARK]
Solution: 1 Mark
We have,
AB = 5.6 cm, AD = 1.4 cm, AC = 7.2 cm and AE = 1.8 cm.
Now, ADDB=1.45.6=14
AEEC=1.87.2=14
⇒ADDB=AEEC
Thus, DE divides sides AB and AC of ΔABC in the same ratio.
∴ By the converse of Basic Proportionality Theorem, we have
DE∥BC