$8.837=14 e^{-0.21 x}$

Step 1 ：Given the equation \(8.837=14 e^{-0.21 x}\).

Step 2 ：Isolate the exponential function on one side of the equation.

Step 3 ：Take the natural logarithm of both sides of the equation to get rid of the exponential function.

Step 4 ：This allows us to solve for x, where a = 8.837, b = 14, c = -0.21.

Step 5 ：Calculate x to get x = 2.190999414663768.

Step 6 ：Simplify the final answer to get \(x = \boxed{2.191}\).