Penjelasan dengan langkah-langkah:

PerSamaan KuadRat

1). x² + x - 72 = 0

x² + 9x - 8x - 72 = 0

x(x + 9) - 8(x + 9) = 0

(x - 8)(x + 9) = 0

x1 = 8 atau x2 = -9

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2). x² - 16x + 60 = 0

x² - 10x - 6x + 60 = 0

x(x - 10) - 6(x - 10) = 0

(x - 6)(x - 10) = 0

x1 = 6 atau x2 = 10

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3). 6x² - 5x - 6 = 0

6x² + 4x - 9x - 6 = 0

2x(3x + 2) - 3(3x + 2) = 0

(2x - 3)(3x + 2) = 0

x1 = 3/2 atau x2 = -2/3

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4). x² - 25 = 0

x² - 5x + 5x - 25 = 0

x(x - 5) + 5(x - 5) = 0

(x + 5)(x - 5) = 0

x1= -5 atau x2 = 5 → x1,x2 = ±5

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5). 3x² - 12x = 0

3x²/3 - 12x/3 = 0

x² - 4x = 0

x(x - 4) = 0

x1 = 0 atau x2 = 4