In the triangle PQR, ∠PQR = 90° and PR = 10 cm. If S is the midpoint of PR, then the length of QS is

In a triangle ABC, D is the midpoint of the side BC; through the point A, PQ is any straight line. The perpendiculars from the points B, C and D on PQ are BL, CM and DN respectively; let us prove that, DL = DM.

ABCD is a squared figure. The two diagonals AC and BD intersect each other at the point O. The bisector of ∠BAC intersects BO at the point P and BC at the point Q. Let us prove that,

In the trapezium ABCD, AB || DC and AB = 7 cm and DC = 5 cm. The midpoints of AD and BC are E and F respectively, the length of EF is

In the triangle ABC, E is the midpoint of the median AD; the extended BE intersects AC at the point F. If AC=10.5 cm, then the length of AF is