D is the mid-point of side BC of a . AD is bisected at the point E and BE produced cuts AC at the point X. Prove that BE : EX = 3 : 1.
Given:- In ΔABC, D is the midpoint of BC and E is the midpoint of AD.
To prove:- BE: EX = 3 : 1
Const:- Through D, Draw DF||BX
Prof:- In ΔEAX and Δ ADF
<EAX = <ADF (Common)
<AXE = <DAF (Corresponding angles)
Then, ΔEAX ~ Δ ADF
So, (Corresponding parts of similar triangle are proportion)
Or, (AE = ED given)
Or, DF = 2EX. ……………(i)
In ΔCDF and ΔCBX (By AA similarity)
SO, (Corresponding parts of similar triangle area proportion)
Or (BD = DC given)
Or BE + EX = 2DF
Or BE = EX = 4EX
Or BE = 4EX – EX
Or BE = 4EX – EX
Or BE = 3EX
Or BE/EX =3/1