Three semicircles each of diameter 3 cm, a circle of diameter 4.5 cm and a semicircle of radius 4.5 cm are drawn in a given figure. Find the area of the shaded region.
Question
How can we show that in a triangle when we join two mid points of adjacent sides of triangle the line obtained by joining the mid points of two adjacent side is equal to the third side of triangle
pls solve problem number b 
In figure AB//CD find
it is given that triangle abc congruent to triangle def, is it true to say that ab=ef? justify