Okay, here we have this:
y=x-1
y=1/2x+1
If we graph we obtain the following:
Now, let's find the solution to the system:
y=x-1
y=1/2x+1
Since the two are equal to "and", then we can equalize them:
x-1=1/2x+1
Let's clear x:
x-2=1/2x
-2=-1/2x
x=4
Now, let's replace to find y:
y=x-1
y=4-1
y=3
Finally we obtain that the solution to the system is: (4,3)