Respuesta :

let x+y=10 be equation (1)
and y=x-4 be equation (2)
from (2)
y=x-4...(3)
sub (3) into (1)
x+(x-4)=10
x+x-4=10
2x=12
x=6
sub (x) into (3)
y=6-4
y=2