tlong d jwab ya kk....
Matematika
TimothyCimory
Pertanyaan
tlong d jwab ya kk....
1 Jawaban
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1. Jawaban whongaliem
L.sisi 2 : L.aiai I2 : L.sisi 3 = a1.t : a2.t : a3 .t
13 : 14 : 15 = a1 : a2 : a3
misal : a1 = 13x ; a2 = 14x ; a3 = 15x
S = 1/2 kll
= 1/2 (13x + 14x + 15x)
= 1/2 (42x)
= 21.x
L.aias = √{ S (S - a1)(S - a2)(S - a3)}
21 = √{21x (21x - 13x)(21x - 14x)(21x - 15x)}
21 = √{21x (8x)(7x)(6x)}
21 = √(7056 x^4)
21 = 84x²
x² = 21/84
x² = 1/4
x = √(1/4)
x = 1/2
L.1 = a1 . t
13 = 13 x . t
1 = x .t
t = 1/x
t = 1 / (1/2)
t = 2 dm
volume = L.alas x t
= 21 x 2
= 42 dm³ .... jawaban : C
catatan : L.alas diasumsikan 21 dm²