Lesson: Geometry - 27

Areas Of Quadrilaterals

[Page 27 of 30]

All five formulas on the list above are useful to know, but you can really get by with only three formulas. First, you don’t need a separate formula for the rectangle because a rectangle is a parallelogram, and thus you can use the parallelogram formula for a rectangle. (The rectangle formula is on the list, however, because it’s such a basic one — which you’ve known since at least middle school — and because it works a bit differently than the parallelogram formula.) And second, because the square is a special type of four quadrilaterals — a parallelogram, a rectangle, a kite, and a rhombus — you don’t really need a special area formula for a square.

The area of a parallelogram is the length of its base times the length of its height. We find the height the same way that we found the height for triangles. The height is the distance from the uppermost angle to the base line.

For parallelogram WXYZ, the length of its base is 5+15=20.

By dropping a perpendicular to the base to get the height, we have made a right triangle. Do the lengths of one leg and the hypotenuse look familiar? We have one of our special triangles: the 5:12:13 Pythagorean ratio. This gives us our height, since we know that VW must be 12.

Now we can find the area, which is 20 × 12 = 240.

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

Problem Solving

Lessons with practice question on math section of the test

Pakistan Army Short Service Regular Commission

Join Pakistan Army through Short Service Regular Commission

All in this Category

You may be interested in

Colleges in Islamabad

A comprehensive list of major colle ...

MA Jinnah Group Of Colleges - Faisalabad

A big name in colleges in Faisalaba ...

Compititive Exam Preparation Books

A list of Books for Compititive Exa ...

Interview Call Winning Resume

Learn how to write Interview Call W ...

ISSB Speech Test

Learn all about ISSB Speech Test. H ...

ISSB Tests

How to deal with ISSB Recruitment t ...

UB University of Balochistan

A popular university in Balochistan ...

Medical Sciences MBBS and BDS

Admission in Medical Sciences MBBS ...

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