Using Law of Cosines find the indicated angle theta

a = 68.01
b = 37.83
c = 42.15

Angle B = theta


I have tried many times. How do I solve this one?

b^2 = a^2 + c^2 - 2abcos(B)

Substituting the values in:
(37.08)^2 = (68.01)^2 + (42.15)^2 - 2(68.01)(42.15)cosB

Solve for cosB:
-5027.0562 = -2(68.01)(42.15) cosB

cosB = .87682....
B = cos^-1(.8762...) = 28.7382 degrees approximately