l and m are two parallel lines intersected by another pair of parallel lines p and q (see Fig. 7.19). Show that `triangle ABC cong triangle CDA`

l and m are two parallel line intersects by another point of parallel lines p and q show that triangle ABC equiv triangleCDA

l and m are two parallel lines. Another pair of parallel lines intersect these lines. Under which congruent rule DeltaABC ~= DeltaCDA .

l and m are two parallel lines. Another pair of parallel lines intersect these lines. Under which congruent rule DeltaABC ~= DeltaCDA .

Line l is the bisector of an angle angle A and B is any point on l. BP and BQ are perpendiculars from B to the arms of angle A (see Fig. 7.20). Show that: (i) triangle APB cong triangle AQB (ii) BP = BQ or B is equidistant from the arms of angle A .

Two parallel lines l and m are intersected by a transversal p (see Fig. 8.15). Show that the quadrilateral formed by the bisectors of interior angles is a rectangle.

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

If m parallel lines in a plane are intersected by a family of n parallel lines, find the number of parallelograms formed.

ABC and DBC are two isosceles triangles on the same base BC (See Fig. ). Show that angleABD = angleACD .

ABC and DBC are two isosceles triangles on the same base BC (See Fig. ). Show that angleABD = angleACD .