## Sunday, January 22, 2012

### Isabel's Textbook Scribe Post ( 4,7,10) and Phytagorean Relationship

4. Estimate the square root of each number, to one decimal place. Check it with a calculator.

72= The estimated square root that I got for 72 is approximately 8.4 and here's how I got it...

STEPS:

1st step: draw/make a number line

2nd step: find out what are the 2 square root numbers that are close to 72 which are 64 and 81 *how I got 64? 8x8 How I got 81? 9x9*

3rd step: write number 64 on the left side, below it write 8, write number 81 on the right side and below it write 9

4th step: estimate a number that is 8 point something but can't be over 9 so I chose 8.4

5th step: double check your answer with a calculator, when I multiplied 8.4 by 8.4 I got 70.56 which us pretty close to 72 but you can also use 8.5

103= The estimated square root that I got for 103 is approximately 10.1 and here's how I got it...
STEPS:

1st step: draw/make a number line

2nd step: find out what are the 2 square root numbers that are close to 102 which are 100 and 121 *how I got 100? 10x10 How I got 121? 11x11*

3rd step: write number 100 on the left side, below it write 10, write number 121 on the right side and below it write 11

4th step: estimate a number that is 10 point something but can't be over 11 so I chose 10.1

5th step: double check your answer with a calculator, when I multiplied 10.1 by 10.1 I got 102.1 which us pretty close to 102

55= The estimated square root that I got for 55 is approximately 7.3 and here's how I got it...
STEPS:

1st step: draw/make a number line

2nd step: find out what are the 2 square root numbers that are close to 55 which are 49 and 64 *how I got 49? 7x7 How I got 64? 8x8*

3rd step: write number 49 on the left side, below it write 7, write number 64 on the right side and below it write 8

4th step: estimate a number that is 7 point something but can't be over 8 so I chose 7.3

5th step: double check your answer with a calculator, when I multiplied 7.3 by 7.3 I got 53.29 which us pretty close to 55 but you can also use 7.4

7. Identify a whole number with a square root between 11 and 12.

The whole number(s) that I identified between 11 ( 121)and 12 (144) are :

How I got 121? 11x11 and how I got 144? 12x12

MIDDLE NUMBERS ..... between 121 and 144 are

122,123,124,125,126,127,128,129,130,131,13 2,133,134,135,136,137,138,139,140,141,142 and 143 and here's how I got it...

10. Kai uses entire can of paint on a square backdrop for the school play. The label in the can states that one can covers 27 squared meters of wall surface. Estimate the backdrop's side length, to one decimal place.

The estimated backdrop's side length is 5.2 meters and here's how I got it...

1st step: draw/make a number line

2nd step: find out what are the 2 square root numbers that are close to 27 which are 25 and 36 *how I got 25? 5x5 How I got 36? 6x6*

3rd step: write number 25 on the left side, below it write 5 , write number 36 on the right side and below it write 6

4th step: estimate a number that is 5 point something but can't be over 6 so I chose 5.2

http://www.funbrain.com/cgi-bin/ttt.cgi?A1=s&A2=4&A3=0

please do comment if I did something wrong or forgot something :)
*sorry I couldn't post the video*

Phytagorean Relationship

1. Answer in a short paragraph and with diagrams:

Explain the Phytagorean Relationship a2+b2=c2

The Phytagorean Relationship is if you add the 2 legs ( a2 and b2) you'll get the hypotenuse (c2). But in order for you to know that your solution might be correct is when the hypotenuse is the biggest number in all of the 3 important parts. The hypotenuse is the longest because it is diagonal/ slanted.

2. Solve for the missing side length

3. Is this a right triangle? Prove it!

It is NOT a right triangle and here's how I got my answer