KUIS [+50]

Penjelasan dengan langkah-langkah:

Persamaan Kuadrat

bentuk umum ax^2 + bx + c = 0 , a ≠ O

..

x^2 + 11x + 28 = 0 , dengan menggunakan metode kuadrat sempurna

maka,

x^2 + 11x + 28 = 0

a = 1

b = 11

c = 28

..

misalkan :

d = b/2a = 11/2(1) = 11/2

e = c – (b^2/4a) = 28 – (11^2 / 4(1)) = 28 – (121/4) = (112 – 121)/4 = -9/4

..

a(x + d)^2 + e = 0

1(x + 11/2)^2 – 9/4 = 0

(x + 11/2)^2 = 9/4

(x + 11/2) = ±√9/4

solusi akar akar

(x + 11/2) = √9/4

(x + 11/2) = 3/2

x = 3/2 – 11/2

x = -8/2 = -4

..

(x + 11/2) = -√9/4

(x + 11/2) = -3/2

x = -3/2 – 11/2

x = -14/2

x = -7

HP = { -4 dan -7 }