How to Find the Slope of a Triangle

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The slope of any angle is the rise over the run. The slope of a triangle measures its “steepness.” Imagine an upright, right-angled triangle. As its hypotenuse reaches the adjacent -- also called the base or the run -- the slope reduces. If you flatten it enough, the triangle becomes a straight line with the hypotenuse, adjacent and the opposite -- also called the rise, or the perpendicular -- falling into a straight line. Conversely, if you pulled the triangle from its peak, or pushed the hypotenuse closer to the opposite, the slope increases. When the hypotenuse is infinitesimally close to the opposite, the slope of the triangle tends to reach infinity. The slope of the triangle, therefore, can vary between the two extremes of zero and infinity. The formula to find the slope of a triangle is given by: Slope = opposite/adjacent

    Measure the length of the opposite side. Let's say it is 5 centimeters.

    Measure the length of the adjacent side. Let's say it is 2 centimeters.

    Divide the opposite by the adjacent to get the slope. In the example, the slope is 5 centimeters divided by 2 centimeters. This divides out to 2.5. What this number means is that for every unit change in the adjacent -- or runs -- the opposite changes or rises by 2.5 times that change.


About the Author

Kiran Gaunle is a freelancer based in New York. He started writing professionally in 2006. He has written research reports for the UN Development Programme and the "Kathmandu Post." Gaunle is working on a book of short stories and a novel. He holds a Master of Arts in international political economy and development from Fordham University.