Question 200748
(1)  x +y  =11
(2) x^2 + y^2 =73
.
from(1) y = (11-x)
.
subst  into (2)
.
x^2 +(11-x)^2 =73
x^2  + (121 -22x +x^2 = 73
2x^2 -22x +48 =0
divide  by  2
x^2 -11x +24 =0
factor
(x-8)(x-3) =0
x= 8 , 3
.
 check
(1) 8+3=11,,,,ok
(2) 64 + 9 = 73 ,,,,,ok