Jawab:

Penjelasan dengan langkah-langkah:

1. x² - 10x + 24 = 0

x² - 2 (5)x + 5² - 5² + 24 = 0

(x - 5)² = 5² - 24

(x - 5)² = 25 - 24 = 1

x - 5 = ±1

x1 = 5 + 1 = 6

x2 = 5 - 1 = 4

2. x² - 4x + 5 = 0

(x + 1) (x - 5) = 0

x + 1 = 0

x1 = 0 - 1 = -1

x - 5 = 0

x2 = 0 + 5 = 5

3. x² + 2x + 5 = 0

a = 1, b = 2, c = 5

x1,2 = (-b ± V(b² - 4ac))/2a

x1,2 = (-2 ± V(2² - 4(1)(5)))/2(1)

x1,2 = (-2 ± V(4 - 20))/2

x1,2 = (-2 ± V(-16))/2

V = akar kuadrat

x² + 2x + 5 = 0 tidak mempunyai akar real, karena kedua akarnya imajiner.