find

t(1 + x²) = x,

rearranging, we get,

t = x/(1 + x²)

substituting this in second equation

x² + [x/(1 + x²)]² = y,

x² + x²/(1 + x²)² = y

Hence dy/dx = 2x + [(1 + x²)². 2x  -  x². 2(1 + x²).2x]/(1 + x²)⁴ 

using x = 2, and evaluating gives,

dy/dx = 488/125

Regards,

Team,

TopperLearning.