slope = m
-If 2 points are given, then y2-y1/x2-x1 (you can choose any point as 1 or 2)
-If you have the equation of the line in the form y = mx + b, the 'm' is the slope.
-If the standard formula is give as Ax + By = C, arange it as the slope-intercept form (y = mx +b), where Ax is mx, By is y, and C is b, (remember that the signs change as you switch sides) and you'll get the slope using the method above.
Hope that helped ! :)