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

Arithmetic

Lessons on Basic to Advance Arithmetic with practice questions

Graphs - Data Interpretation

Lessons and practice questions for Data Interpsection - Graphs

GRE Biology

Find what is GRE Biology and how to appear in the test

All in this Category

You may be interested in

Colleges in Sukkur

Find a comprehensive list of major ...

Colleges in Peshawar

Find a comprehensive list of major ...

Business School Admission Process

A detailed discussion about how you ...

Making Millions

How to become a successful person i ...

Pakistan Army Selection and Recruitment Tests

Join Pakistan Army. How it is possi ...

ISSB Projective Personality Tests

Learn all about ISSB Projective Per ...

Universities in sindh

A comprehensive list of universitie ...

AIMC Allama Iqbal Medical College

AIMC Allama Iqbal Medical College i ...

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