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Kelas 10 Matematika
Bab Persamaan Kuadrat

(2x + 3y) (ax + by) = px² + 2xy - 15y²
2ax² + 2bxy + 3axy + 3by² = px² + 2xy - 15y²
2ax² + (3a + 2b) xy + 3by² = px² + 2xy - 15y²

3b = -15
b = -15/3
b = -5

3a + 2b = 2
3a + 2 . (-5) = 2
3a = 2 + 10
a = 12/3
a = 4

p = 2a
p = 4 . 2
p = 8