Odpowiedzi

2010-04-16T20:58:13+02:00
5 = x²-10x+30
x²-10x+30-5 = 0
x²-10x+25 = 0
a = 1 b = -10 c = 25
Δ = b²-4ac
Δ = 100-100
Δ = 0
x = -b/2a
x = 10/2
x = 5