Respuesta :

For this type of questions we use the formula os the area of a sector:

[tex]AS=\text{ }\pi r^2\cdot\frac{\alpha}{360}[/tex]

Substituting we get

[tex]AS=\pi(12)^2\frac{180}{360}=\pi(144)\frac{1}{2}=72\text{ }\pi[/tex]

RELAXING NOICE
Relax