Respuesta :

Answer:

[tex]238\ in^{2}[/tex]

Step-by-step explanation:

we know that

The radii divide the pentagon into five isosceles triangles each with a center angle of 360/5 = 72 degrees

so

The area of the regular pentagon is equal to the area of one isosceles triangle multiplied by 5

step 1

Find the area of one isosceles triangle

Applying the law of sines

[tex]A=\frac{1}{2}(10)(10)sin(72\°)=47.55\ in^{2}[/tex]

step 2

Find the area of the regular pentagon

[tex]47.55*(5)=237.76\ in^{2}[/tex]

Round to the nearest whole square inch

[tex]237.76=238\ in^{2}[/tex]