Question

Tolong dijawab nomor 6, 9, 12, dan 13. PAKE CARA!!!
Yang ngasal dilaporkan, yang bagus, dikasih yang terbaik

Answer 1

6. L EBC = 1/2 x EB x BC = 66
1/2 x 12 x BC = 96
6 BC = 96
BC = 96/6
BC  = 16 cm

AE = CD = 20-12 = 8cm

Luas jajar genjang AECD = 8 x 16 = 128 cm²

9. AB = AE+EF+FB = 32
x+3+x+1+3x-2 = 32
5x+2 = 32
5x = 32-2
5x = 30
x = 30/5
x = 6

AE = x+3 = 6+3 = 9 cm
EF = x+1 = 6+1 = 7 cm (DC)

DE = √AD²-AE² = √15²-9² = √225-81 = √144 = 12 cm

Luas trapesium = 1/2 x (AB+DC) x DE = 1/2 x (32+7) x 12 = 234 cm² (A)

12. OC = 1/2 AC = 1/2 x 24 = 12 cm
OF = √13²-12² = √169-144 = √25 = 5 cm
jadi FE = 2 x 5 = 10 cm
Luas AECF = 1/2 x 10 x 24 = 120 cm²

DO = √15²-12² = √225-144 = √81 = 9 cm
BD = 2xDO = 2x9 = 18 cm
L ABCD = 1/2 x 18 x 24 = 216cm²

Luas arsir = 216 - 120 = 96 cm²


13. =(8.3-6)+(9.5-6) =18+39 = 57 cm2