1)(x+y)/(x-y)+(x-y)/(x+y)=13/6
(x+y)/(x-y)=a
a+1/a=13/6
6a²-13a+6=0,a≠0
D=169-144=25
a1=(13-5)/12=2/3
{(x+y)/(x-y)=2/3⇒3x+3y=2x-2y⇒x=-5y
{xy=5
-5y²=5
y²=-1 нет решения
a2=(13+5)/12=3/2
{(x+y)/(x-y)=3/2⇒2x+2y=3x-3y⇒x=5y
{xy=5
5y²=5
y²=1
y1=-1⇒x1=-5
y2=1⇒x2=5
(-5;-1);(5;1)