Question

Calculate this using the property,
exterior angle = sum of interior remote angles (except the angle of linear pair)
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Answer 1

/ ACE + / ACD = 180°

:. / ACD = 180° - 130°

:. / ACD = 50°

in triangle ADC , AD = DC

:.by isosceles triangle theorem ,

/ DCA = / DAC

:. / DAC = 50°.

NOW ,

in triangle ADC,

/ A + / D + / C = 180°

:. 50° + / D + 50° = 180°

:. / D = 180° -