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Kelas 10 Matematika
Bab Fungsi Kuadrat

(-4, 0), (-2, 0) dan (0, -8)

y = a (x - x1) . (x - x2)
-8 = a (0 + 4) . (0 + 2)
-8 = a . 4 . 2
a = -8/8
a = -1

y = a (x - x1) . (x - x2)
y = (-1) . (x + 4) . (x + 2)
y = (-1) . (x² + 6x + 8)
y = -x² - 6x - 8

✩✩ A ✩✩