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

А) - 11 * х ² + 5 * х + 54 = 0 D = b ^ 2 - 4ac = 5 ^ 2 - 4·(-11)·54 = 25 + 2376 = 2401x1 = ( - 5 - √ 2401 ) / ( 2 · ( - 11 ) ) = ( - 5 - 49 ) / ( - 22 ) = -54 / ( - 22 ) x2 = ( -5 + √2401 ) / ( 2·(-11) ) = ( - 5 + 49 ) / ( - 22 ) = 44 / ( - 22 ) Б) 5 * х² - 15 * х=05 * x * ( x - 3 ) = 0 x = 0 x - 3 = 0 x = 3 В ) 81 * х² = 64 x ^ 2 = 64 / 81 x = 8 / 9 x = - 8 / 9 Г) х ² - 7 * х + 6 = 0D = b ^ 2 - 4ac = (-7) ^ 2 - 4·1·6 = 49 - 24 = 25x1 = ( 7 - √25 ) / ( 2 · 1 ) = ( 7 - 5 ) / 2 = 2 / 2 = 1x2 = ( 7 + √25 ) / ( 2·1 ) = ( 7 + 5 ) / 2 = 12 / 2 = 6