y = mx + b is the slope intercept form of a linear equation.
m is the slope and b is the y intercept.
To find the y intercept you want to find the point where the graph crosses the y axis. On this graph you can see that it is 1.
The slope is rise/run. This is 2/1, so slope is 2.
Putting these into the equation we get y = 2x + 1
This is not an option because the answers are in standard form.
Changing to standard form we get 2x - y = -1
Letter C
