Answer:
D.
Step-by-step explanation:
<FIL and <AIN are Vertical angles.
Vertical angles are always congruent.
Congruent means the same or equal.
A = 1/2 bh
A = 1/2 (21)(8)
A = 1/2 (168)
A = 84
8/9 * 1/4 = 8/36 division of fractions is equal to the multiplication of the reciprocal