Question

can u plz answer this

Answer 1

hey...
first in triangle DCE and FBE , we have
angleCED=angleBEF ( vertically opposite angles)
CE=BE ( since E is the mid point of CB )
angleC= angleEBF ( alternate interior angles)
therefore triangle CED is congruent to triangle BEF .
so, by CPCT , DC is equal to BF but DC is also equal to AB ( opposite sides of a parallelogram)
so, DC = BF= AB
AF =AB + BF
since AB= BF
so, AF= 2AB..
Hence Proved