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We know that opposite angles of a parallelogram are equal so ∠ABC=∠ADC ⇒ ∠ADC = 125° also we know that BC is transversal so ∠ADB + ∠DCB = 180° .....................(co-interior angle) but ∠DCA=28° so ∠ACB= 180°-(125°+28°) = 180°- 153° ∠ACB= 27° but AD║BC with transversal AC so ∠DAC = 27° ....................(alternate interior angle)
Answers & Comments
so
∠ABC=∠ADC ⇒ ∠ADC = 125°
also we know that
BC is transversal
so
∠ADB + ∠DCB = 180° .....................(co-interior angle)
but ∠DCA=28°
so
∠ACB= 180°-(125°+28°)
= 180°- 153°
∠ACB= 27°
but AD║BC with transversal AC
so
∠DAC = 27° ....................(alternate interior angle)
<cda=125
<cda+<dca+<dac=180
125+28+<dac=18=
<dac=27