pakr cara ya pliss bantu no 6 7 8 11 12 13

9.
L = TT × r × r = 22/7 × 21 × 21 = 9702/7 = 1386 (A)
11.
L1 = p × l = 8 × 20 = 160
L2 = TT × r × r = 3,14 × 4 × 4 = 50,24 cm
160 - 50,24 = 109,76 cm
12.(itu sebenarnya sama dgn 1 lingkaran)
L = TT × r × r = 3.14 × 10 × 10 = 314 cm
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