x+2y=5 3x+y=5

Subtract 3x from both sides of the second equation:

y = 5 - 3x

 

Substitute this into the first equation:

x + 2(5 - 3x) = 5

or

x + 10 - 6x = 5

-5x = -5

x = 1

 

Substitute this back into the equation for y

y = 5 - 3*1

y = 2

.