Respuesta :
Respuesta:
[tex] {x}^{2} - {y}^{2} = (x + y)(x - y) [/tex]
[tex] {y}^{2} - 81 = {y}^{2} - {9}^{2} = (y + 9)(y - 9)[/tex]
Respuesta:
[tex] {x}^{2} - {y}^{2} = (x + y)(x - y) [/tex]
[tex] {y}^{2} - 81 = {y}^{2} - {9}^{2} = (y + 9)(y - 9)[/tex]