Lesson: Geometry - 21

30°/60°/90° Triangles

[Page 21 of 30]

A triangle where the angles are 30°, 60°, and 90°. If you draw an altitude in an equilateral triangle, you will form two congruent 30º- 60º- 90º triangles. Starting with the sides of the equilateral triangle to be 2, the Pythagorean Theorem will allow us to establish pattern relationships between the sides of a 30º- 60º- 90º triangle. These relationships will be stated here as "short cut formulas" that will allow us to quickly arrive at answers regarding side lengths without applying trigonometric functions, or other means.

Another triangle that you're almost sure to see on your standardized test is the 30°/60°/90° triangle. Often, you'll see it when an equilateral triangle is divided into two triangles of equal size. Learn the side-length ratio for the 30°/60°/90° triangle and you'll save yourself many calculations on test day.

If we set x as the length of the shortest side (the side opposite the 30° angle), then the side opposite the 60° angle has length x √3, and the hypotenuse has length 2x.

Hint

Back Next

Next to display next topic in the chapter.

Test Prep Lessons With Video Lessons and Explained MCQ

Large number of solved practice MCQ with explanations. Video Lessons and 10 Fully explained Grand/Full Tests.

Quantitative Aptitude Reasoning English General Knowledge Picture Patterns
More for You
MCQ with question Explanations Scholarships and Financial Aid

Data Sufficiency

Easily crack the most logical section of the GMAT

Geometry

How to solve Geometry questions on math section of the test

ISSB Direction Sens Questions

Learn about ISSB Direction Sens Questions to deal with

All in this Category

You may be interested in

Colleges in Multan

A comprehensive list of best colleg ...

Colleges in cities of Khyber Pakhtoonkhwa

Comprehensive lists of colleges in ...

Pakistan International and Economic Issues

A comprehensive list of essays on P ...

Test-Preparation Articles

Acquire the most effective Test Pre ...

GRE Psychology

Find all about GRE Psychology with ...

SAT Reasoning Test

SAT Reasoning - a general test for ...

Engineering Colleges Universities in Balochistan

A list of Engineering colleges and ...

Management Sciences

Universities offering programs in M ...

About us

EntryTest.com is a test preparation service for students seeking successful career.

About Disclaimer

Quick Test Prep

NUST NET IBA Karachi SAT LUMS LCAT LSE

 

NTS GAT NTS NAT GMAT GRE ACT

Study Abroad

Education Abroad Business Schools MS in USA