Step-by-step explanation:
since both shapes are totally symmetric, a few answers are obvious :
(1) F2 = F1 = 50°
(3) B1 = D1 = 20°
last but not least, D2 = B2.
using the fact that the sum of all angles in a triangle is always 180°.
and that the sum of all angles sind a single point on one side of a line is also always 180° :
in the triangle CDF the inner angle C is
C = 180 - 20 - 50 = 110°.
therefore, C1 = 180 - 110 = 70°
E1 = 90° (a major rule for the diagonals of a kite).
D2 = 180 - 90 - 70 = 20°
and so, B2 = 20°
(2) D2 = 20°
(4) B2 = D2 = 20°
