Question

$left { {{4x-2y=4} atop {2x+22y=25}} right.$
$left { {{y-2x=2} atop {5x^2-y=1}} right.$

Answer 1

$left { {{4x-2y=4}(:2) atop {2x+22y=25}} right. = textgreater left { {{2x-y=2} atop {2x+22y=25}} right.= textgreater 2x=2+y \ 2+y+22y=25 \ 23y=23 \ y=1 \ \ 2x=2+1 \ 2x=3 \ x=3/2$


$left { {{y-2x=2} atop {5x^2-y=1}} right.= textgreater y=2+2x \ 5x^2-(2+2x)=1 \ 5x^2-2-2x=1 \ 5x^2-2x-3=0 \ D=4+ 60=64=8^2 \ x_1=(2+8)/10=1 \ x_2=(2-8)/10=- frac{3}{5} \ \ y=2+2*1 \ y_1=4 \ y=2-2* frac{3}{5}=2- frac{6}{5} \ y_2= frac{4}{5}$