Question

Triangle abc is an isosceles triangle in which ab =ac.d,e,f are the midpoints of the side bc,ac,ab. Respectively.prove that de=df.

Answer 1

in this diagram,
ab=ac
so, ab=5cm and ac=5cm.
the d,e and f are midpoints
so,
de=2.5cm
ef=2.5cm
df=2.5cm
finally this shows that
de=df