Answer:
It is -1.
Explanation:
To start off y=mx+b is the formula for this type of problem. y and x are variables, m is the slope, and b is the y-intercept. Since you need to identify the y-intercept, all you need to do is look at the end of the equation to find the y-intercept. In this case it is -1, since -1 is b.
Hope that helps!