Respuesta :

Answer: 2x+3 and -1

Step-by-step explanation:

a)

[tex]A=\pi r^2 = 4\pi x^2 + 12\pi x + 9\pi\\r^2 = 4x^2 + 12x + 9\\r^2 = (2x+3)^2\\r = 2x+3[/tex]

b) Radius has to be greater than 0, so 2x + 3 > 0

2x > -3

x > -1.5

So least possible integer value is -1