Respuesta :

7 = s²

s = x + 2

7 = (x + 2)²

7 = (x + 2)(x + 2)

7 = x² + 2x + 2x + 4

7 = x² + 4x + 4

x² + 4x = 3

X1=-2-/7,x2=2+/7 is the answer