Ini gambar jelas nya… bantu pake cara​

b. 477,75cm²

d. 5cm

b. 42

Penjelasan dengan langkah-langkah:

L1 = p × l

= 30cm × 12cm

= 360cm²

L2 = 3(½πr²)

= 3 (½ × 3,14 × 5cm × 5cm)

= 3 × 39,5cm²

= 117,75

L = L1 + L2

= 360cm² + 116,75cm²

= 477,75cm²

L.arsiran = 100,375cm²

p = 15cm

l = 8cm

L1 = p × l

= 15 × 8

= 120cm²

L.arsiran = L1 – L2

100,375cm² = 120cm² + L2

L2 = 120cm² – 100,375cm2

L2 = 19,625cm²

L2 = πr²

19,625 = 3,14r²

r² = 19,625/3,14

r² = 6,25cm

r = √6,25

r = 2,5cm

d = 2r = 2 × 2,5cm = 5cm

L = 1.386cm²

L = πr²

1.386 = 22/7r²

r² = 1.386×7 / 22

r² = 441

r = √441

r = 21cm

d = 2r = 2 × 21cm = 42cm