Define the tax function T(x) for each income bracket before the rebate.

Step 1: Define the tax function T(x) for each income bracket before the rebate. Let x be the annual income. For income less than R55 000: No tax is paid. T_gross(x) = 0 for x < 55000. For income between R55 000 and R85 000 (inclusive): Tax is 9% of the total income. T_gross(x) = 0.09x for 55000 x 85000. For income above R85 000: Tax consists of a fixed