Respuesta :

x-y=10
2x-y=17
So to start
x=10+y
now replace x in the second equation
2(10+y) -y=17
20+2y-y=17
20+y=17
y=17-20
y=-3
Now replace y with -3 in any equation to find x

x-(-3) = 10
x+3=10
x=10-3
x=7