Hello,Originally Posted by jacs
to a). Both triangles have the same base: XY and the same height, because XY divides the height of ABC in 2 equal parts.
to b) XC divides (ABC) in 2 equal areas.
to c) Because area(AXY) = area(XYC) and area(ABC) = 2 * area(AXC) therefore area(ABC) = 4 * area(AXY)
(The three midparallels of a triangle divide the triangle in 4 congruent triangles, similar to the great one)
I've attached a copy of your diagram to demonstrate how I calculated.