Question

Resolva os sistemas:
a) { x²+y²=5
    {x²-y²=1


b) {x²+y²=13
   {x . y=6

Answer 1

a) x²=1+y²
(1+y²)+y²=5
2y²-4=0
y=√2

x²-(√2²)=1
x²-2=1
x=√3