Respuesta :

dhiab

Answer:

Step-by-step explanation:

x² + y² = 5 .....(1)

y = 2x....(2)

put y = 2x in (1) :

x² + (2x)² =5

x²+4x² =5

5x² = 5

x² = 1

so : x = 1 or x = -1

if x = 1   y = 2

if x = -1  y = - 2

two solutions : (1;2)   , ( - 1 ; -2 )