Odpowiedź:
x + a = b/x dla x ≠ 0 i a = 15 , b = - 50
x + 15 = - 50/x | * x
x² + 15x = - 50
x² + 15x + 50 = 0
a = 1 , b = 15 , c = 50
Δ = b² - 4ac = 15² - 4 * 1 * 50 = 225 - 200 = 25
√Δ = √25 = 5
x₁ = ( - b - √Δ)/2a = (- 15 - 5)/2 = - 20/2 = - 10
x₂ = (- b + √Δ)/2a = (- 15 + 5)/2 = - 10/2 = - 5
Odp: B
