In short, to find the area of a triangle, all you need to do is take the area of a rectangle formula ($A=bh$) and divide it by 2. Thanks to all authors for creating a page that has been read 2,710,329 times. A triangle is a three-sided polygon.We will look at several types of triangles in this lesson. Here’s an example of a video I found particularly helpful while writing this article: You can also check out Khan Academy, a free website that offers a bunch of videos, lessons, and practice problems for an array of math subjects, including triangles and area. How can you figure out the area of a triangle? hbspt.cta.load(360031, '4efd5fbd-40d7-4b12-8674-6c4f312edd05', {}); Have any questions about this article or other topics? How can I find the area of an isosceles right triangle? Without more information, you can't find an exact value. Our new student and parent forum, at ExpertHub.PrepScholar.com, allow you to interact with your peers and the PrepScholar staff. Area of a Triangle. Although it uses the trigonometry Sine function, it works on any triangle, not just right triangles . This is how to find the area of a rectangle—pretty simple, really. Numerous other formulas exist, however, for finding the area of a triangle, depending on what information you know. Thus, we can use one of these right triangles to find the length of the height line. Examples: find the area of a triangle. The area of this equilateral triangle is 16√3 square units. This article was co-authored by our trained team of editors and researchers who validated it for accuracy and comprehensiveness. However, when the triangle is not a right-angled triangle there are multiple different ways to do so. Given Equilateral Triangle. You can also write the formula as: ½ x base x height You can find the area of a triangle by multiplying the base by the height and then dividing that number by 2. Calculate the area of the triangle pictured below. So the formula we could use to find the area of a triangle is: (base x height) ÷ 2. Finding the area of a triangle can be tricky, even if you know the formula. To find the area, multiply the base by the height, and then divide that number by 2. Every shape in math—that is, every square, rectangle, triangle, parallelogram, trapezoid, etc.—has an area, or a certain amount of space it occupies. Solve for the value of the area. For this, you’ll need to know the area of triangle formula. The red line represents the length of the base (call it b if you want) and the blue line represents the length of the height. The 5 Strategies You Must Be Using to Improve 160+ SAT Points, How to Get a Perfect 1600, by a Perfect Scorer, Free Complete Official SAT Practice Tests. Mary Jane Sterling is the author of Algebra I For Dummies and many other For Dummies titles. How to Get the Area of a Triangle. Note that none of these triangles are drawn to scale. This involves trigonometry. Method 1. SAT® is a registered trademark of the College Entrance Examination BoardTM. For example, you might have a triangle with a base measuring 5 cm long, and a height measuring 3 cm long. We are told that the base is 9 and the height is 4 (remember that the height is the line that's perpendicular to the apex, or highest point, of the triangle and the base). The most common way to find the area of a triangle is to take half of the base times the height. How to find the area of an oblique triangle when given two sides and an angle? To learn how to calculate the area of a triangle using the lengths of each side, read the article! Heron's formula can be used to find the area of a triangle when the length of the 3 sides of the triangle are known. The other (far quicker) option for finding the area of a rectangle, however, is to multiply the length (5 units) by the width (2 units); this will also get you 10. In this guide, we'll go over how to find the area of a triangle and give you sample problems and tips you can use to further sharpen your skills. Perpendicular means at right angles. This means we'll have 4 on one side of the height line and 4 on the other: Now, look closely at this equilateral triangle. Using these measurements, you can find the area of the triangle. All rights reserved. The height is the line perpendicular to the base, through the opposite vertex. It is simply half of b times h. Area = 12 bh (The Triangles page explains more) The most important thing is that the base and height are at right angles. Area is the total amount of space a 2-D shape (or flat surface) takes up. For example, look at the 30-60-90 right triangle in the following figure. Nearly as easy as these to calculate it possible to calculate the area of right... Act Target Score should you be Aiming for: where p is half the perimeter a! 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