Question

Решите уравнения
А) -11х²+5х+54=0
Б) 5х²-15х=0
В)81х²=64
Г)х²-7х+6=0

Answer 1

А) -11х²+5х+54=0
     11х²-5х-54=0
     D = b²-4ac = 25+2376 = 2401
    √D = 7
    X1 = (-b+√D)/2a = (5+7)/22 = 6/11
    Х2 = (-b-√D)/2a =  (5-7)/22 = - 1/11

Answer 2

Б) 5х²-15х=0

Answer 3

5х(х-3) = 0

Answer 4

5х = 0 или х-3 = 0

Answer 5

Х1 = 0, Х2 = 3