side-length-of-a-square-from-the-diagonal

Geometry Teachers Never Spend Time Trying to Find Materials for Your Lessons Again!

Join Our Geometry Teacher Community Today!

http://geometrycoach.com/Geometry-Lesson-Plans/?pa=MOOMOOMATH

Example problem in which the side length of a square is calculated from the diagonal length.

Transcript

Let's look at a square Think about a square. Earlier in the unit we talked about the diagonal of a square. You have a square with a diagonal of 10 centimeters. What is the length of each side? Let's mark our angles. We have 90 degrees angles, because it is a square, and we know that a square the diagonal bisects the angle so it is a 45-45-90 triangle. Let's pull this triangle out. If this side is 10, which is the diagonal, this angle will be 90 degrees, and these two are 45 degrees. Remember the rules, the rules for a 45-45-90 = x, x x√2, two sides are the same so it is a x√2 problem. Let's take 10 is equal to √2 (10=√ 2)and solve for x. Divide both sides by √ 2 because you are getting smaller, you are getting the hypotenuse. Next I need to rationalize that so I'm dividing 10 by √ 2, and I have to clear the radical out, so multiply by √ 2/√ 2 , and I get 2 on the bottom, and 10√ 2, and simplify that to 5√ 2 So each side is going to have a length of 5√ 2. That is how you find the length of each side of a square from the diagonal length of a square. Each side will measure 5√ 2. That is how you find the length of each side given the diagonal. Inside a square you have a 45-45-90 right triangle

You may also enjoy...

Finding sides right triangle given diagonal length

https://www.youtube.com/watch?v=323AORpGobM

Finding perimeter of a square

https://www.youtube.com/watch?v=CJiSTAuGCmk

-~-~~-~~~-~~-~-

Please watch: "Study Skills Teacher's Secret Guide to your Best Grades"

https://www.youtube.com/watch?v=f3bsg8gaSbw

-~-~~-~~~-~~-~-

Tagged under: Mathematics (Field Of Study),square,finding side length,geometry,diagonal length,Length (Dimension),Diagonal,math,maths,trig,45-45-90 triangle

Clip makes it super easy to turn any public video into a formative assessment activity in your classroom.

Add multiple choice quizzes, questions and browse hundreds of approved, video lesson ideas for Clip

Make YouTube one of your teaching aids - Works perfectly with lesson micro-teaching plans

1. Students enter a simple code

2. You play the video

3. The students comment

4. You review and reflect

* Whiteboard required for teacher-paced activities

With four apps, each designed around existing classroom activities, Spiral gives you the power to do formative assessment with anything you teach.

Quickfire

Carry out a quickfire formative assessment to see what the whole class is thinking

Discuss

Create interactive presentations to spark creativity in class

Team Up

Student teams can create and share collaborative presentations from linked devices

Clip

Turn any public video into a live chat with questions and quizzes

Tried out the canvas response option on @SpiralEducation & it's so awesome! Add text or drawings AND annotate an image! #R10tech

Using @SpiralEducation in class for math review. Student approved! Thumbs up! Thanks.

Absolutely amazing collaboration from year 10 today. 100% engagement and constant smiles from all #lovetsla #spiral

Students show better Interpersonal Writing skills than Speaking via @SpiralEducation Great #data #langchat folks!

Dr Ayla Göl
@iladylayla

A good tool for supporting active #learning.

The Team Up app is unlike anything I have ever seen. You left NOTHING out! So impressed!