Hitunglah nilai x (jika ada) yang memenuhi persamaan nilai mutlak 1. |4-3x|=|-4| 2. 2x + |3x-8|=4 3. 2x+|3x-8|=-4 4. 5 |2x-3|=2|3-5x| 5. 2x + |8-3x| = |x-4|
Matematika
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Pertanyaan
Hitunglah nilai x (jika ada) yang memenuhi persamaan nilai mutlak 1. |4-3x|=|-4| 2. 2x + |3x-8|=4 3. 2x+|3x-8|=-4 4. 5 |2x-3|=2|3-5x| 5. 2x + |8-3x| = |x-4|
1 Jawaban
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1. Jawaban ErikCatosLawijaya
Mapel : Matematika
Kelas : X SMA
Bab : Mutlak
Pembahasan :
|4 - 3x| = |-4|
|4 - 3x| = 4
4 - 3x = 4
4 - 4 = 3x
3x = 0
x = 0
4 - 3x = -4
3x = 4 + 4
3x = 8
x = 8/3
Hp : {0 , 8/3}
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2|3x - 8| = 10
|3x - 8| = 5
3x - 8 = 5
3x = 13
x = 13/3
3x - 8 = -5
3x = 3
x = 1
Hp : {1 , 13/3}
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2x + |8 - 3x| = |x - 4|
|x - 4| - |8 - 3x| = 2x
x - 4 - 8 + 3x = 2x
4x - 12 = 2x
4x - 2x = 12
2x = 12
x = 6
x - 4 - 8 + 3x = -2x
4x - 12 = -2x
4x + 2x = 12
6x = 12
x = 2
Hp : {2 , 6}
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5|2x - 3| = 2|3 - 5x|
(10x - 15)² = (6 - 10x)²
(10x - 15)² - (6 - 10x)² = 0
(10x - 15 + 6 - 10x)(10x - 15 - 6 + 10x) = 0
(-9)(20x - 21) = 0
-180x + 189 = 0
180x = 189
x = 189/180
x = 21/20
Hp = {21/20}
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2x + |3x - 8| = -4
|3x - 8| -4 - 2x
(3x - 8)² = (-4 - 2x)²
(3x - 8)² - (-4 - 2x)² = 0
(x - 12)(5x - 4) = 0
x = 4/5
x = 12
Hp : {4/5 , 12}
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2x + |3x - 8| = 4
|3x - 8| = 4 - 2x
(3x - 8)² = (4 - 2x)²
(3x - 8)² - (4 - 2x)² = 0
(x - 4)(5x - 12) = 0
x = 12/5
x = 4
Hp : {12/5 , 4}