Решение задания во вложении (=
1) y(14-y)=-72<span>14y-=72 *(-1)</span><span>-14y-72=0</span><span>D=-ac=49+72=121</span><span>x=-k+/a=-7-11=-18</span><span>x_2=-k-=-7+11=4</span> Ответ: 18 и -4 ;<span> </span>
<span>a^2 - 3a + b^2 +3b -2ab =
</span>a^2 - 2ab + b^2 -3a +3b =
(a-b)^2 -3(a-b) =
(a-b) (a-b-3)