Question

Решите систему уравнений:

x+y=1

x^2+y^2=25

Answer 1

Решение во вложении.

Answer 2

спасибо

Answer 3

Ответ:

(4;-3), (-3;4)

Объяснение:

$left { begin{array}{lcl} {{x+y=1,} \ {x^{2} +y^{2} =25;}} end{array} right.Leftrightarrow left { begin{array}{lcl} {{x=1-y,} \ {(1-y)^{2} +y^{2} =25;\}} end{array} right.Leftrightarrow left { begin{array}{lcl} {{x=1-y,} \ {1-2y+y^{2}+y^{2} -25=0; }} end{array} right.$

$Leftrightarrowleft { begin{array}{lcl} {{x=1-y,} \ {2y^{2} -2y-24=0;}} end{array} Leftrightarrowright.left { begin{array}{lcl} {{x=1-y,} \ {y^{2} -y-12=0;}} end{array} right.Leftrightarrow left { begin{array}{lcl} {{x=1-y,} \ {left [ begin{array}{lcl} {{y=-3,} \ {y=4;}} end{array} right.} end{array} right.$

$Leftrightarrow left [ begin{array}{lcl} {left { begin{array}{lcl} {{x=4,} \ {y=-3;}} end{array} right.{} \ {left { begin{array}{lcl} {{x=-3,} \ {y=4.}} end{array} right.}} end{array} right.$