If x = 27 yards, y = 120 yards, and z = 123 yards, what is the sine of b?

Using the Law of Cosines
Renaming sides X, Y and Z
A= 27 yards B = 120 yards, and C = 123 yards, what is the sine of B?
cos (B) = (a^2 + c^2 -b^2) / (2 * a * c)
cos (B) = (27^2 +123^2 -120^2) / (2*27*123)
cos (B) = (729 + 15,129 - 14,400) /  6,642
cos (B) = 1,458 / 6,642
cos (B) = 0.2195121951220
cos (B) = 77.32 degrees