Question

metodo de sustitucion x+y=13 y x-y=7

Answer 1

x+y=13
x-y=7

x= 13-y

x-y= 7
13-y-y= 7
-2y= 7-13
y= -6/-2
y= 3

x= 13-y
x= 13-3
x= 10

salu2.

suerte... :)