Question

if angle ABC are congruent angle DEF and angle angle A =50° and angle F =60° then find angle B

Answer 1

angle b = 70°
as ABC and DEF are congruent so A=D, E=B and C=F

Answer 2

here
,ATQ
A=D,B=E,C=F Because they are congruent
A=50,F=60
As ,F=C
IN triangle ABC
A+B+C=180
50+60+B=180
110+B=180
B=180-110
B=70degree

Hope it helps you 
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