Verify the system of linear equations in cosA, cosB, and cosC.

_______ c cosB + b cosC = a

c cosA ______ + a cosC = b

b cosA + a cosB _______ = c

Then use Cramer's Rule to solve for cosC, and use the result to verify the Law of Cosines, c^2 = a^2 + b^2 - 2abcosC