The discussion focuses on calculating the derivative and tangent line for the equation y^4 + xy = 2x^2 - 7x + 7. The derivative is derived through implicit differentiation, resulting in the expression dy/dx = (4x - y - 7) / (4y^3 + x). At the point (1, 1), the derivative evaluates to -4/5. Consequently, the equation of the tangent line T(x) is determined to be T(x) = -4/5(x - 1) + 1, simplifying to T(x) = -4/5x + 1/5. This process illustrates the steps involved in finding the tangent line to a curve defined by an implicit function.