-- Look at the places where the line crosses the 'x' axis and the 'y' axis. Between those two points, it goes forward 2 units, but only rises 1 unit. So the slope of the line is 1/2 .
-- Look again at the point where the line crosses the y-axis. At that point, y=1 . That's the "y-intercept".
Now you have the slope and y-intercept of the line.
The equation of ANY straight line is
y = (slope)x + (y-intercept) .
You know what they both are, so you can easily write
y = 1/2 x + 1 .
Is that one of the choices ? Yes it is. Good enough for me. That must be the correct one.
