
Although you may have met this sometime in middle school math and may now take it for granted, it is actually a brilliant mathematical device. The technical name of the x-y plane is the Cartesian plane, named after its inventor, Mr. Let’s get a bit philosophical for a moment. Again, I highly recommend performing this visual check every time you calculate slope. Even a rough sketch would verify that, yes, the slope should be negative. Your sketch, of course, does not need to be this precise. Here’s a sketch of this particular calculation: Whenever you find a slope, I strongly suggest doing a rough sketch, just to verify that the sign of the slope (positive or negative) and the value of the slope are approximately correct.

Slope is definitely something you need to understand for the GMAT Quantitative section. Now, rise/run = –3/7 - that’s the slope. For the sake of argument, we’ll say that’s the order - (–2, 4) is the “first” and (5, 1) is the “second.” The rise is the change in height, the change in y-coordinate: 1 – 4 = –3 (notice, we had to do second minus first, which gave us a negative here!) The run is the horizontal change, the change in x-coordinate: 5 – (–2) = 5 + 2 = 7 (remember: subtracting a negative is the same as adding a positive!). Once we have rise & run, divide them, rise divided by run, to find the slope.įor example, suppose our points are (–2, 4) and (5, 1). The run is the horizontal change - the change in the x-coordinate (again, second minus first). The rise is the vertical change - the change in y-coordinate (second point minus first). It actually doesn’t matter which one we say is the first and which one, the second: all that matters is that we are consistent.


To calculate rise and run, first have to put the two points in order. There is very algebraic formula for the slope, and if you know that, that’s great! If you don’t know that formula, or used to know it and can’t remember it, I will say: fuhgeddaboudit! Here’s a much better way of thinking about slope. Slope is a measure of how steep a line is. If these problems make your head spin, you have found the right post. What is the value of b?ģ) A line that passes through (–1, –4) and (3, k) has a slope = k. This article was written for you by Sunny, one of the tutors with Test Prep Academy.Here are a set of practice GMAT questions about the Cartesian plane.ġ) What is the equation of the line that goes through (–2, 3) and (5, –4)?Ģ) The line y = 5x/3 + b goes through the point (7, –1). Looking to get ready for the SAT? We can help with SAT Prep

The slope of the line between two points (x1, y1) and (x2, y2) is given by: Slope is not only a very key concept for linear equations, but it is also important for differential calculus. The slope of a line describes its steepness, incline or grade. To find the midpoint of those same two points (x1, y1) and (x2, y2), all you need to do is to average the x and y values and express them as an ordered pair: In Geometry, the midpoint is the middle point of a line segment, which is equidistant from both endpoints. To find the distance between two points, given the coordinates of these two points are (x1, y1) and (x2, y2), the distance D between the points is given by: Finding the distanceĭistance is a numerical description of how far apart objects are. As graphs become more and more complicated, you will be asked to apply and use all three of these pieces of information. From the points, we can determine the distance, and the midpoint and the slope of the segment connecting them. From a graph, we can easily find two points. In mathematical aspect, graphs are more than just beautiful images.
