Let's start off with a simple y-intercept form.
y=mx + b
b represents the y intercept so we can substitute it with 2.
y = mx + 2
the point we are given, (1,1) is really just an x and y value. We can also substitute this into the equation.
y = x + 2
Now that we have some type of equation, we can convert it to the form shown in the answer choices by subtracting y from both sides.
0 = x - y + 2
Hope this helps!