Respuesta :
(8x + x)^2
= (8x + x)(8x + x)
= 8x(8x + x) + x(8x + x)
= 64x^2 + 8x^2 + 8x^2 + x^2
= 81x^2
OR
(8x + x)^2
= (9x)^2
= 9x * 9x
= 81x^2
= (8x + x)(8x + x)
= 8x(8x + x) + x(8x + x)
= 64x^2 + 8x^2 + 8x^2 + x^2
= 81x^2
OR
(8x + x)^2
= (9x)^2
= 9x * 9x
= 81x^2