Hasil dari kuadrat sempurna ×2+4×-5=0

Persamaan Kuadrat

x² + 4x – 5 = 0

x² + 4x + 4 = 5 + 4

(x + 2)² = 9

x + 2 = ± √9

x = -2 ± 3

akar persamaan :

x1 = -2 + 3 = 1

x2 = -2 – 3 = -5