Solve for remaining sides and angles of a triangle with side

Solve for remaining sides and angles of a triangle with side a = angle A = 30.0 degree.

a = 60 cm

c = 40 cm

A = 30 degree

Now law of cosines,

a = sqrt[b^2 + c^2 - 2bc*cosA]

60 = sqrt[b^2 + 40^2 - 2*b*40*cos30]

b^2 - 69.28*b - 2000 = 0 ========> b = 91.2 cm

Then b = sqrt[a^2 + c^2 - 2ac*cosB]

91.2 = sqrt[60^2 + 40^2 - 2*60*40*cosB] = sqrt[5200 -4800*cosB]

B = 130.5 degree

THen C = 180 - 30 - 130.5 = 19.5 degree