mohon pakai jalannya no 9 dan 10

semoga membantu.. pahami baik baik

Mapel : Matematika
Kelas : IX SMP
Bab : Kesebangunan dan Kekongruenan

Pembahasan :
9.

CD/AC = DE/AB
6/(6 + 4) = 8,1/AB
6/10 = 8,1/AB
3/5 = 8,1/AB
3AB = 40,5
AB = 13,5 cm

Jawaban : B

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10.

BD/AB = DE/AC
8/(8 + 4) = 6/AC
8/12 = 6/AC
2/3 = 6/AC
2AC = 18
AC = 9 cm

BE = √[BD² + DE²]
BE = √[8² + 6²]
BE = √[64 + 36]
BE = √100
BE = 10 cm

BC = √[AB² + AC²]
BC = √[12² + 9²]
BC = √[144 + 81]
BC = √225
BC = 15 cm
BE + EC = 15
10 + EC = 15
EC = 5 cm

Jawaban : D