that evolution occurs is a demonstrated fact. We've sen it happen, in real time, in living populations. These observations include extinction and speciation events, which by definition represent macroevolution.
Carbon dating is accurate over a range of about 2 to 45 thousnad years,when applied to appropriate samples (i.e., organic remains that incorporate carbon isotopes from the atmosphere by respiration).
Even if we threw out all evidence from evolution and carbon dating, there is still abundant evidence demonstrating the earth is on the order of 4.5 bilion years old (for example, radio-isochron dating using isoptes other than C14, such as Potassium/argon).