Page 64 - Inovasi Modul Matematika Bangun Datar Segi Empat_Lusi Malini_Neat
P. 64
Keliling = 2 (27 cm)
Keliling = 54 cm
4. Diketahui : AE = 8 cm
BD = 30 cm
2
Luas = 420 cm
Ditanya : keliling ?
Jawab :
L = × d × d 2
1
L = × AC × BD
420 = × AC × 30
420 = 15 AC
AC = = 8
EC = AC – AE = 28 cm – 8 cm = 20 cm
AD = √8 5 = √64 5 = √ 89 = 7
DC = √ 5 = √ 5 4 = √6 5 = 5
Keliling = 2 (AD + DC)
Keliling = 2 (17 cm + 25 cm)
Keliling = 2 (42 cm)
Keliling = 84 cm
2
5. Diketahui : luas = 300 cm
AC = 24 cm
BC = 20 cm = AB
Ditanya : AD ?
Jawab :
62
Bangun Datar Segiempat - VII