If D,E and F are respectively, the mid-points of AB,AC and BC in `DeltaABC`, then BE+AF is equal to

If D, E, F are respectively the mid-points of AB, AC and BC respectively in a Delta ABC, " then " vec (BE) + vec(AF) =

In DeltaA B C , D, E and F are respectively the mid-points of sides AB, BC and CA. Show that DeltaA B C is divided into four congruent triangles by joining D, E and F.

In DeltaA B C , D, E and F are respectively the mid-points of sides AB, BC and CA. Show that DeltaA B C is divided into four congruent triangles by joining D, E and F.

D, E and F are respectively the mid-points of sides AB. BC and CA of triangleABC . Find the ratio of the areas of triangleDEF and triangleABC .

In Delta ABC, AB = 5cm , BC = 8 cm and CA = 7cm. If D and E are respectively the mid-points of AB and BC, determine the length of DE.

E and F are respectively the mid-points of equal sides AB and AC of DeltaA B C (see Fig. 7.28). Show that BF = C E .

D, E and F are respectively the mid-points of the sides BC, CA and AB of a DeltaA B C . Show that (i) BDEF is a parallelogram. (ii) a r\ (D E F)=1/4a r\ (A B C) (iii) a r\ (B D E F)=1/2a r\ (A B C)

In a DeltaABC,D,E and F are respectively the mid-points of BC, CA and AB. If the lengths of side AB, BC and CA are 7 cm, 8 cm and 9 cm respectively, find the permeter of DeltaDEF.

If D, E and F be the middle points of the sides BC,CA and AB of the DeltaABC , then AD+BE+CF is

ABCD is a square. E and F are respectively the mid-points of BC and CD. If R is the mid-point of EF, prove that ar (DeltaAER) = ar (DeltaAFR) .