Question

Решить систему
4x^2+4xy+y^2=25
2x-y=3

Answer 1

$left { {{4x^{2}+4xy+y^{2}=25}atop {2x-y=3}} right.\\left { {{(2x+y)^{2}=25} atop {2x-y=3}} right.\\1)+left { {{2x+y=5} atop {2x-y=3}} right.\\4x=8\x_{1}= 2\y_{1} =5-2x=5-2*2=5-4=1\\2) +left { {{2x+y=-5} atop {2x-y=3}} right.\\4x=-2\x_{2}= -0,5\y_{2}=-2x-5=-2*(-0,5)-5=1-5=-4$

Ответ : (2 ; 1) , (- 0,5 ; - 4)