# Thread: Find length of diagonal across 8.5-by-11 inch sheet

1. ## Find length of diagonal across 8.5-by-11 inch sheet

Standard letter paper is 8.5 inches wide and 11 inches long. To the nearest tenth of an inch, what is the diagonal distance d across the paper?

2. Hint: Apply the Pythagorean Theorem.

Eliz.

3. ## Find length of diagonal across 8.5-by-11 inch sheet

Can somebody else than Eliz be more willing to show some work so I can see if i did it correctly. Eliz. Thanks for the "tip" but you didn't really help much.

4. SaeLK, if you're unfamiliar with the Pythagorean Theorem, then you need classroom help...or at least (if you're not too busy or tired) look it up: use Google

Have a nice day.

5. Originally Posted by SaeLk
Can somebody else than Eliz be more willing to show some work so I can see if i did it correctly.
If you've done the exercise, then please show your work. We'll be glad to check to see if you did this correctly.

Note: Since you used some method other than the Pythagorean Theorem (or, which is the same thing, the Distance Formula), please state what method you used when you reply.

Thank you.

Eliz.

6. $a^{2}+b^{2}=c^{2}$

I'll let you write the letters on the paper and maybe figure out how to fold it just right.

7. ## Find length of diagonal across 8.5-by-11 inch sheet

8.5^2 in + 11^2 in.

a^2 + b^2 = d ?

d = 193.25 or d = 13.901.....

72.25 + 121 = 193.25

This method I used to get the answer.

but my first one was 11 in - 8.5 in. = 2.5 in
then 11 + 2.5 = 13.5 in was my answer.

I'm not sure which answer is the correct one. or even if i have a correct answer.

8. Hey, well done Saelk!

The math gurus like to see:
let d = diagonal; then:
d^2 = 8.5^2 + 11^2
d^2 = 72.25 + 121
d^2 = 193.25
d = sqrt(193.25)
d = ~13.90143....
d = 13.9 (nearest 10th)

Now take a sheet of 8.5 by 11, draw the diagonal,
then measure it with your ruler: 13.9 looks good ?

And if you CUT along the diagonal, you're left with 2 triangles,
same size and with right angle, right?

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•