1. Сума двох чисел=12.а їх добуток =35 складіть систему рівнянь для визначення цих чисел...

$\left \{ {{x+y=12} \atop {x*y=35}} \right.\\\\\left \{ {{x=12-y} \atop {(12-y)*y=35}} \right.\\\\\left \{ {{x=12-y} \atop {12y-y^{2}-35=0 }} \right.\\\\\left \{ {{x=12-y} \atop {y^{2}-12y+35=0 }} \right.\\\\1)\left \{ {{y=5} \atop {x=12-5}} \right.\\\\\left \{ {{y=5} \atop {x=7}} \right. \\\\2)\left \{ {{y=7} \atop {x=12-7}} \right.\\\\\left \{ {{y=7} \atop {x=5}} \right.$

Ответ : (5 , 7) , (7 , 5)

$\left \{ {{x-y=2} \atop {x*y=48}} \right. \\\\\left \{ {{x=y+2} \atop {(y+2)*y=48}} \right.\\\\\left \{ {{x=y+2} \atop {y^{2}+2y-48=0 }} \right.\\\\1)\left \{ {{y=-8} \atop {x=-8+2}} \right.\\\\\left \{ {{y=-8} \atop {x=-6}} \right.\\\\2)\left \{ {{y=6} \atop {x=6+2}} \right.\\\\\left \{ {{y=6} \atop {x=8}} \right.$

Ответ : (- 6 ; - 8) , ( 8 , 6)