let ABC be a triangle with AB=AC. If D is the mid-point of BC, E the foot of the perpendicular drawn from D to AC, F is the mid-point of DE. Prove that AF is perpendicular to BE.

Let ABC be a triangle with AB=AC. If D is the midpoint of BC,E is the foot of the perpendicular drawn from D to AC, and F is the midpoint of DE, then prove that AF is perpendicular to BE.

If D id the mid-point of the side BC of a triangle ABC and AD is perpendicular to AC , then

In a Delta ABC, if D is the mid point of BC and AD is perpendicular to AC, then cos B=

ABC is a triangle and D is the mid-point of BC .The perpendiculars from D to AB and AC are equal.Prove that the triangle is isosceles.

D is the mid-point of side AB of the triangle ABC.E is the mid-point of CD and F is the mid-point of AE. Prove that 8 xx " area of " (DeltaAFD) = " area of " Delta ABC

In o+ABC,D is the mid-point of BC and ED is the bisector of the /_ADB and EF is drawn parallel to BC cutting AC in F. Prove that /_EDF is a right angle.

Let ABC be an isosceles triangle with AB=AC and let D,E,F be the mid-points of BC,CA and AB respectively.Show that AD perp FE and AD is bisected by FE .