Complex sentence: RSS for this model is\\ sum--^\\ left (y---\\ hat\\ right) ^ 2, which is equivalent to\\ sum--^\\ left (y---\\ bar\\ right) ^ 2, the TSS.
Split into simpler sentences: RSS for this model is\\ sum--^\\ left (y---\\ hat\\ right) ^ 2. This is equivalent to\\ sum--^\\ left (y---\\ bar\\ right) ^ 2, the TSS.