tolong yaa kak, jangan asal asalan, harus pakai cara !!

AC / AB = x / 6
4 / 3 = x / 6
x = 8 cm

CB = √(6² + 8²)
CB = 10 cm

Perbangan Luas Δ
½ • AB • AC = ½ • CB • AE
6 • 8 = 10 • AE
AE = 48 : 10
AE = 4,8 cm

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AD / AE = DE / BC
3 / 5 = 5,4 / BC
1 / 5 = 1,8 / BC
BC = 9 cm