Question

x, x, 12; obtuse

Answer 1

x^2 + x^2 > 12^2

2 x^2 > 144

x^2 > 72 --> need to solve this for x.

Answer 2

2.44?

Answer 3

Wouldn't it be a less than instead of greater than since the triangle is obtuse?

Answer 4

2.44 wouldn't actually work because there's an extra restriction now that it's obtuse. You also need \(x+x > 12\) because if that wasn't true, then the two smaller sides wouldn't be able to connect to each other.

Answer 5

@ The King --> I was trying to say that I thought you had the theorem backwards on that other problem. I will look at the solution you cranked out.

If the CORRECT theorem is used, there will be no problem.

Answer 6

So it's not 2.44? I am so lost.

Answer 7

The \(x+x > 12\) is merely the triangle inequality theorem: If the sides of your triangle are \(a, b, c\) the the length of \(a+b\) is greater than the length of \(c\). So 2.44 would actually be two small. You need a value greater than 6.

Answer 8

However, you also need to use the theorems that Directrix posted that says \(a^2+b^2 < c^2\) so \(x^2+x^2<12^2 \Longrightarrow 2x^2 < 144\)

Answer 9

Can you solve for \(x\) from there?

Answer 10

I give up. Maybe I should just go for tutoring tomorrow morning.

Answer 11

Just pretend the < sign is an = sign until you solve for x. When you solve for x, merely replace the = sign with < again.

Answer 12

Well, if I could have chance to work through the ENTIRE problem with you without someone else mixing another approach into the work, we might be able to get somewhere. So, I don't know. When the King is finished with this problem, I will try to help.

Answer 13

Go ahead. I'll stay out.

Answer 14

Alright.

Answer 15

x^2 + x^2 > 12^2

2 x^2 > 144

x^2 > 72 --> need to solve this for x.

x > (+/-) 6 √ 2

The negative root does not apply here.

x > 8.48, say 8.5

Pick a number x such that x > 8.48.

Answer 16

Post it here.

Answer 17

8.48

Answer 18

Is 8.48 GREATER THAN 8.48 ?

(Pick a number x such that x > 8.48.) This is from above.

Answer 19

Pick a number > 8.48.

I need to find the instructions for what we are doing.

Answer 20

Any number??

Answer 21

YES

Answer 22

9 would be good

Answer 23

I cannot find the instructions for the original problem?

Answer 24

Whatever they are, 9, 9, 12 could be the sides of this obtuse triangle. There are others.

Answer 25

this is so confusing for me..

Answer 26

Could I just try one last one?

Answer 27

Let's start in a new thread with the instructions. I don't know what we do after getting the sides. Plus, you owe me a meY@l. lol

Answer 28

hahah :P

Answer 29

What about that other thread tonight where I was working for you lol

Answer 30

I fell asleep on my desk lol. The other night I was up till 3 studying for a different test.

Answer 31

Not what I mean. The first problem from tonight about the acute triangle.

Answer 32

I'd like to point out that a 9, 9, 12 triangle is an acute triangle, where the measure of angle ABC is approximately 84 degrees if the length of AB=BC=9.

Answer 33

new question posted!