tolong jawab no7 dan 8 dengan jawaban

7) L1 = ½ × π × r² = ½ × 22/7 × 7 × 7 = 77 dm²
L2 = 2 × ½ × a × t = 2 × ½ × 7 × 4 = 28 dm²
Lttl = L1 + L2 = 77 + 28 = 105 dm²

8) LP = s × s = 21 × 21 = 441 dm²
Llngkrn = π × r² = 22/7 × 10,5 × 10,5 = 346,5 dm²
Lb = LP - L lingkaran = 441 - 346,5 = 94,5 dm²