Respuesta:
2 y -7
Explicación paso a paso:
(2x + 5)² + 3 = 84
(2x + 5)² = 84 - 3 = 81
2x + 5 = √81
I. 2x + 5 = 9
2x = 9 - 5 = 4
x1 = 4 / 2 = 2
I. 2x + 5 = -9
2x = -9 - 5 = -14
x2 = -14 / 2 = -7
