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Mapel : Matematika
Tentang : Bangun Datar
Pertanyaan yg diajukan : 1
Pembahasan :

Diketahui :
- Luas (L) : 1.256 cm²

Ditanya :
- Keliling (K)

Cara :

[tex]l = \pi \times {r}^{2} \\ \\ 1256= 3.14 \times {r}^{2} [/tex]

[tex] {r}^{2} = \frac{1256}{3.14} \\ \\ {r}^{2} = 400[/tex]

[tex]r = \sqrt{400} \\ \\ r = 20 \: cm[/tex]

[tex]k = 2 \times \pi \times r \\ \\ k = 2 \times 3.14 \times 20[/tex]

[tex]k = 6.28 \times 20 \\ \\ k = 125.6 \: cm[/tex]

Jawaban : 125,6 cm

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Hopefully this is the best for you.

MAKE BRAINLY GREAT AGAIN!!!

Heil Manstein!

[tex]l = \pi \times {r}^{2} \\ 1256 = 3.14 \times {r }^{2} \\ \frac{1256}{3.14} = {r }^{2} \\ {r}^{2} = 400 \\ r = \sqrt{400 } \\ r = 20 \\ k = 2 \times \pi \times r \\ k = 2 \times 3.14 \times 20 \\ k = 125.6cm[/tex]