Question

А)х^2+х-56=0 б)5х^2+9х+4=0 решите надо

Answer 1

$\sf\displaystyle x^2+x-56=0\\D=1+224=225=15^2\\x_{1,2}=\frac{-1\pm 15}{2}=\left |{ {{7} \atop {-8}} \right.$

ответ: $-8;7$

$\sf\displaystyle 5x^2+9x+4=0\\D=81-5\cdot4\cdot 4=1\\x_{1,2}=\frac{-9\pm 1}{10}=\left |{ {{-1} \atop {-0,8}} \right.$

ответ: $-1;-0,8$