Respuesta :

Answer:

≈ 41.1 cm²

Step-by-step explanation:

The shaded area (A) is calculated as

A = area of sector - area of Δ ABC

   = πr² × [tex]\frac{90}{360}[/tex] - ( [tex]\frac{1}{2}[/tex] × 12 × 12 )

   = π × 12² × [tex]\frac{1}{4}[/tex] - (6 × 12)

   = 144π × [tex]\frac{1}{4}[/tex] - 72

    = 36π - 72

    ≈ 41.1 cm² ( to 1 dec. place )