pakai jqlan no. 26.

L1 = p x l
     = 12 cm x 8 cm
     = 96 cm²
L2 = 1/2 x a x t
     = 1/2 x 8 cm x 3 cm
     = 12 cm²

Luas gabungan = 96 cm² + 12 cm²
                          = 108 cm²

luas=(8 x 12)+(1/2 x 8 x 3)=96+12=108 cm²(c)