-X² + 2x + 24 (gimana ya tolong dunx)

-x^2 + 2x + 24 = 0
(-x + 6)(x + 4) = 0
-x + 6 = 0 atau x + 4 = 0
x = 6 atau x = -4

Bab Persamaan Kuadrat
Matematika SMP Kelas VIII

-x² + 2x + 24 = -(x² - 2x - 24)
                     = - (x² - 6x + 4x - 24)
                     = - (x (x - 6) + 4 (x - 6))
                     = - (x + 4) (x - 6)
                     = (x + 4) (-x + 6)

jika = 0, maka

(x + 4) (-x + 6) = 0
x + 4 = 0
x = -4

atau

-x + 6 = 0
- x = - 6
x = 6