Odpowiedzi

2010-02-03T17:06:25+01:00
2x-2x-2x=x+4
2x-2x-x-2x=4
-3x=4/:-3
x=4/-3
2010-02-03T17:10:18+01:00
X(x-2)-2x = x+4
x²-2x-2x-x = 4
x²-5x = 4
x²-5x-4 = 0
Jest to równanie kwadratowe, skorzystamy z delty
ax²+bx+c = 0

Δ = b²-4ac
Δ = 25-4*1*(-4)
Δ = 25+16
√Δ = √41

x1 = (-b-√Δ)/2a
x1 = (5-√41)/2

x2 = (-b+√Δ)/2a
x2 = (5+√41)/2

Odp. x = 5-√41)/2, lub x = (5+√41)/2.
1 5 1
2010-02-03T17:16:28+01:00
X(x-2)-2x=x+4
x(x-2)-2x-x=4
x-2-2x=4
x-2x=4=2
-x=6/*(-1)
x=-6
?????