Answer:
a = 12.4 units
Step-by-step explanation:
We can use trigonometric ratio; Cosine
Cosine = Adjacent/ Hypotenuse
Cos B = a/c
But; c = 13 and a =?
B = 16° 45' = 16.75°
Therefore;
Cos 16.75 ° = a/13
a = 13 × cos 16.75°
= 12.4 units
