It doesn't matter whether it's convex or not. The sum of the interior angles of any 13-sided polygon is (11 x 180°) = 1,980°.
The sum of the measures of the interior angles of a convex 13-gon is calculated using the formula (n - 2) × 180°, resulting in 1980 degrees. ;
The sum of the measures of the interior angles of a convex 13-gon is 1980°. This is calculated using the formula ( n − 2 ) × 18 0 ∘ , where n is the number of sides. For a 13-gon, this gives us 11 × 18 0 ∘ = 198 0 ∘ .
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Diketahui:-Uang Sinta = Rp60.000-Uang Indra = Rp60.000 + Rp20.000 =IDR 80.00 -Uang Adi = 2 x Rp60.000 = Rp120.000-Uang Joko = 1/3 x Rp60.000 =Rp20.000Jumlah Uang mereka berempat : Uang Total = 60.000 + 80.000 + 120.000 + 20.000 = Rp280.000Jawabannya adalah : Rp280.000