A straight line parallel to any side of any triangle divides other two sides (or the extended two sides)__________ .

The straight line parallel to the parallel sides of a trapezium divides _______ other two sides.

XY is a straight line parallel to the side MT of the parallelogram MNOT , which intersects the side MN at X and the side TO at Y.E and F are two points on XY . If ME and TF are extended, they intersect at P and the extended NE and OF intersect each other at Q . Prove that PQ||MN||TO .

The straight line parallel to the side BC of DeltaABC intersects the sides AB and AC at the points D and E respectively. Then (AB)/(BD)=(AC)/(CE) .

If the length of the sides of two triangles are in proportion, then two triangles are ______________

If the area of the square drawn on any side of a triangle is equal to the sum of the areas of the squares drawn on the other two sides of the triangle ,then the triangle will be right-angled triangle, the opposite angle of the greatest side of which will be "......................" .

Prove that three times the square of any side of an equilateral triangle is equal to four times the square of the altitude.

Prove by the theorem of Thales that the third side of a triangle is parallel to the line segment obtained by joining the mid-points of any two sides of the triangle and is half in length of its third side.

One angle of a triangle is 120^(@) and length of three sides. Are in A.P. If largest side of the triangle is 7 unit, length of one of the other two sides is-