 This video is called Find the Slope Using Graphs. So remember, slope is finding the steepness of a line and you can remember before you do any calculating that when you look at a graph and from left to right the line is going down you can remember it will have a negative slope and from left to right if the line is going up like our second graph we will have a positive slope. So no matter what this answer, the slope for my first graph should have a negative and the answer the slope for my second graph should be a positive number. One nice thing about having the line on a graph is you don't actually have to use a slope formula or do any sort of calculation. If you have a high quality grid paper where it's evenly spaced and a line on that grid paper you can simply use two points on your line. So you can see this one right here and this one right here, they're points on a line and they also cross the grid paper at intersections of that grid. So we are going to simply use the graph to count how far up or down do we have to go from the point on the left to the point on the right. It's easiest if you just start with the point on the left and then we'll do our counting to move to the right. So on the second graph we'll start here and count over to here. It's important to remember slope is a fraction, it's the rise over the run. So the numerator tells you how far up or down the points move where the denominator tells you how far from the left to right the points move. So when we count start with the point on the left and it looks like to get to the point on the right we're going to have to count down we're going to go down one, two, three, four and to the right two. So let's try that again from the point on the left to the point on the right we're going down one, two, three, four and to the right two. So down four would be a negative four to the right two would be a positive two so you end up with the slope of negative two for my first graph. Now this makes sense because we said the answer should be negative because from left to right the line is going down. Now let's look at our second picture it looks like we have a point on the line right on the origin zero zero and then another point at three comma two. Both of those points again are on the line but they also on the grid paper are where the grids intersect. Remember this method of counting only works if you have grid paper that's evenly spaced and the line is on it perfectly. Sketches doesn't tend to work so well you have to be pretty careful so let's go ahead to find the slope. We're going to create our fraction remember that it is rise over the run so we're going to go from left to right and count how far up and how far over do we have to go from to get from the left point to the right so from here I'm going to count up two and to the right three again from this point it was up to to the right three so the numerator is up to the denominator represents to the right three so the second line has a slope of a positive two thirds and that makes sense because we said at the beginning because this line goes up from the left to the right our slope should be positive that something you should check when you take a test or a quiz make sure if it's going up from left to right your answer is positive if it's going down from left to right your answer is negative that should be an easy thing to get right every single time