Respuesta :

y = x - 2 
x + y = 10

Substitute "x - 2" for y into the second equation:
x + (x - 2) = 10
2x - 2 = 10
2x = 12
x = 6

Now that we have x, we can plug it into either equation to get the value for y:

6 + y = 10
y = 4

or 

y = 6 - 2
y = 4