Question

Tentukan akar-akar dari persamaan kuadrat dari :
1. (x – 1)x = 2x - 2
2. (2 - x)( x + 3) = 2(x – 2)
3. (x + 2)2x – 2(x + 2) = 0

Answer 1

Kalikan kemudian sederhanakan masing masing variabel,
1. (x - 1)x = 2x - 2
=> x² - x - 2x + 2 = 0
=> x² - 3x + 2 = 0
=> (x - 1)(x - 2) = 0        x₁ = 1 , x₂ = 2
2. (2 - x)(x + 3) = 2(x - 2)
=> 2x + 6 - x² - 3x - 2x + 4 = 0
=> -x² - 3x + 10 = 0
=> x² + 3x - 10 = 0
=> (x - 2)(x + 5) = 0        x₁ = 2 , x₂ = -5
3. (x + 2)2x - 2(x + 2) = 0
=> (x + 2)(2x - 2) = 0      x₁ = -2 , x₂ = 1