Soal matematika kelas 8 smp
Penjelasan dengan langkah-langkah:
a)
K.persegi = 4 × 14 = 56
L.persegi = 14 × 14 = 196
K. 3/4 lingkaran = 3/4 × 2 × 22/7 × 7 = 33
L. 3/4 lingkaran = 3/4 × 22/7 × 7 × 7 = 115,5
K = 56 – 33 = 23
L = 196 – 115,5 = 80,5
b)
K.persegi panjang = (2 × 10) + (2 × 15) = 50
L. persegi panjang = 15 × 10 = 150
K. 2 set. lingkaran
= (1/2 × 3,14 × 15) + (1/2 × 3,14 × 10)
= 23,55 + 15,7 = 39,25
L. 2 set. lingkaran
= (1/2 × 1/4 × 3,14 × 225) + (1/2 × 1/4 × 3,14 × 100)
= 88,3125 + 39,25 = 127,5625 atau 127,56
K = 50 + 39,25 – 15,7 = 73.55
L = 150 + 127,56 – 39,25 = 238,31
Semoga benar
Jawaban:
a. luas = 14 x 14 – 0.75 x 22/7 x 7 x 7 = 196 – 115.5 = 80.5 cm²
keliling = 0.75 x 22/7 x 14 + 14 = 33 + 14 = 47 cm
b. luas = 15 x 10 + 0.5 x 3.14 x 7.5 x 7.5 = 150 + 88.3125 = 238.3125 cm²
keliling = 15 + 0.5 x 3.14 x 15 + 3.14 x 10 = 15 + 23.55 + 31.4 = 69.95 cm