Step 1 :Substitute \(x = 0\) into the function \(T(x) = -7 + 23e^{-0.034 * x}\) to find the initial temperature of the soda.
Step 2 :Calculate \(T(0) = -7 + 23e^{-0.034 * 0} = -7 + 23e^0 = -7 + 23 * 1 = -7 + 23 = 16\).
Step 3 :\(\boxed{16}\) degrees Celsius is the initial temperature of the soda.
Step 4 :Substitute \(x = 20\) into the function \(T(x) = -7 + 23e^{-0.034 * x}\) to find the temperature of the soda after 20 minutes.
Step 5 :Calculate \(T(20) = -7 + 23e^{-0.034 * 20} = -7 + 23e^{-0.68} = -7 + 23 * 0.506 = -7 + 11.638 = 4.638\).
Step 6 :Rounding to the nearest degree, the temperature of the soda after 20 minutes is approximately 5 degrees Celsius.
Step 7 :So, \(\boxed{5}\) degrees Celsius is the temperature of the soda after 20 minutes.