Question

please help me with this. No. 4. I will be very thankful to you

Answer 1

In given fig.
In∆DCB & ∆DAB,
angle BDA= angle DBC [given]
DB=DB [common]
AC=AC [common]
hence∆DCB is congruent to ∆DAB [by A.S.S. congruence rule]........
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