I don't know how to do this

Answer:
a) 2x + 3; b) 0
Step-by-step explanation:
Area = [tex]4\pi x^2+12\pi x+9\pi =\pi (4x^2+12x+9)=\pi (2x+3)^2[/tex]
Area = [tex]\pi r^2[/tex]
a) radius r = 2x + 3
b) 2x + 3 > 0
x > -3/2
The least possible integer value of x is 0