No 21 sj yah bsk dikumpul ^_^

di soal terdapat 2 bangun

Luas bangun 1 = p × l
= 12 cm × 8 cm
= 96 cm²

Luas bangun 2 = ½ × alas × tinggi
= ½ × (17 cm - 12cm ) × 8 cm
= ½ × 5 cm × 8cm
= ½ × 40 cm
= 20 cm²

Luas bangun diatas
= Luas bangun 1 + Luas bangun 2
= 96 cm² + 20 cm²
= 116 cm² (C)

No. 21
Di situ terdapat bangun trapesium siku siku

Luas Trapesium = 1/2 × (a + b) × t
= 1/2 × (17cm+12cm) × 8cm
= 1/2 × 29 cm × 8 cm
= 14,5 cm × 8 cm
= 116 cm^2 (C)

Semoga membantu !!!