Answer:
Step-by-step explanation:
<u>B is the midpoint of AC. It means:</u>
<u>And we have a common side BD:</u>
a) As per above we only have two sides congruent and this information is not sufficient to state the triangles ABD and CBD are congruent.
b) <u>In addition to the two sides we also have:</u>
With this additional information we have three sides congruent, so the triangles are congruent by SSS postulate.