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

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


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