9514 1404 393
Answer:
(c) 18.55
Explanation:
The law of sines tells you ...
y/sin(106°) = 15/sin(51°)
y = 15×sin(106°)/sin(51°)
y ≈ 18.55
_____
The same kind of proportion can find x:
x = 15×sin(23°)/sin(51°)
x ≈ 7.54
Please note that the question posted here asks for the value of y. The value of x and the complete triangle solution are provided as a courtesy to those who may be asked for other values in this triangle.