hitunglah luas daerah bangun berikut

L1 = a×t÷2 = 13×8÷2 = 13×4 = 52 cm²
L2 = a×t÷2 = 5×12÷2 = 5×6 = 30 cm²
L3 = a×t÷2 = 3×4÷2 = 3×2 = 6 cm²
L total = L1 + L2 + L3 = 52+30+6= 88 cm²

L∆¹ = (13×8):2 =52
L∆² = (12×5):2 = 30
L∆³ = (4×3):2 = 6
L seluruhnya = 52+30+6 = 88 cm