First you need to simplify the equation.
y + 3 = 2(x - 1)
y + 3 = 2x - 2
Then you need to put that into slope-intercept form (y = (slope)x + (y intercept))
y + 3 = 2x - 2
-3 -3
y = 2x - 5
The slope is the coefficient of x, so 2 is the slope of the line.
