What are the first few steps to solving this system by the substitution method?

Question

xy=3
x^2+y^2=10

Answer 1

Substitute 3/x for y in the second equation, and solve the resulting equation for x.

x^2 + 9/x^2 = 10

x^4 - 10x^2 + 9 = 0

(x^2 - 1)(x^2 - 9) =

x = 1, -1, 3 or -3.