Hitung keliling daerah yg diarsir berikut.

Kell = kell 1/4 lingkaran + 9 + 13 + kell 1/4 Lingkaran + 9 + 13
= 1/4 × 2 × π × r + 9 + 13 + 1/4 × 2 × π × r + 9 +13
= 1/4 × 2 × 22/7 × 7 + 22 + 1/4 × 2 × 22/7 × 7 + 22
= 11 + 22 + 11 +22
= 66 cm

L persegi = pxl
=20x16
= 320cm²
L 1/4 lingk + L 1/4 lingk = 1/2 x phi x r²
= 1/2 x22/7 x49
= 77cm²
Luas diarsir= 320-77
= 243cm²