The subject who was diagnosed with primary hypothyroidism was given levothyroxine (synthetic T 4 ). After 2 months of treatment, her TSH values decreased by 96.38 % and her T 4 levels increased by...

The subject who was diagnosed with primary hypothyroidism was given levothyroxine (synthetic T₄). After 2 months of treatment, her TSH values decreased by 96.38 % and her T₄ levels increased by 879.4 %. Explain why her TSH levels decreased and T₄ increased.