Answer:
Option d. 18.7 units
Explanation:
step 1
we have
B=17° 55'=17+55/60=17.92°
C=98° 15'=98+15/60=98.25°
step 2
Find the measure of angle A
∠A+∠B+∠C=180°
substitute
∠A+17.92°+98.25°=180°
∠A=180°-(17.92°+98.25°)=63.83°
step 3
Applying the law of sines
c/sin(C)=a/sin(A)
substitute the values
c/sin(98.25°)=17/sin(63.83°)
c=sin(98.25°)*17/sin(63.83°)
c=18.7 units