Question

love the following parallelograms and find the value of unknown A,B,C

Answer 1

first we find the fourth side (say D) by linear pair axiom
75°+ D = 180°
D = 105°
now angle b = angle d =105°(opp. angles of llgm are equal)
now angle a + angle b= 180°( sum of angle of adjacent angles is 180°)
a+ 105°= 180°
a= 75°
again a=c = 75°
hence a = 75°
b= 105°
c =75°