ada yg tahu pls jwb ya pake cara

a = 16
b = 4

Sn = n/2 ( 2a + ( n - 1 ) b )
S₂₆ = 26/2 ( 2(16) + ( 26 - 1 ) 4 )
S₂₆ = 13 ( 32 + 25(4) )
S₂₆ = 13 ( 32 + 100 )
S₂₆ = 13 ( 132 )
S₂₆ = 1716 buah [ opsi. D ]

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