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Surds In A Triangle Pythogaras

Iv put the question in a attachment. I know this is pythagorases theorm I would usually try to find x but theres 3 numbers :O which ones do i square?

Maths Surds.docx10.5KB

Reply 1

TenOfThem

Original post by ChocoholicCox

Iv put the question in a attachment. I know this is pythagorases theorm I would usually try to find x but theres 3 numbers :O which ones do i square?

It would be useful if you told us what the question was asking

I am going to assume that the question asks you to show that the triangle is Right Angled

If that is the case you need to show that the numbers given work for Pythagoras

Reply 2

ChocoholicCox

Original post by TenOfThem

Oh yeah sorry basically yeah it said show that triangle XYZ is a right angled triangle thanks

Reply 3

TenOfThem

Original post by ChocoholicCox

Oh yeah sorry basically yeah it said show that triangle XYZ is a right angled triangle thanks

Then, it is as I said in the previous post

Reply 4

Lord Frieza

Yeah so use any of the numbers in Pythagoras' theorem and you will get the number you didn't use.

If the numbers are identical then you've shown Pythagoras' theorem.

Reply 5

ChocoholicCox

Thanks I did 2 root 3²+ root 13² and got 19 and then did 5²= 25

but then do i square root the 25 to get 5? :/

(edited 10 years ago)

Reply 6

TenOfThem

Original post by ChocoholicCox

Thanks I did 2 root 3²+ root 13² and got 19 and then did 5²= 25

but then do i square root the 25 to get 5?

No, you need to check your working as 19 is incorrect

Reply 7

ChocoholicCox

Original post by TenOfThem

No, you need to check your working as 19 is incorrect

oh right thx ill check oh right yeah its 12 stupid me :/

OMG this is so easy now thanks :biggrin:

Reply 8

TenOfThem

Original post by ChocoholicCox

oh right thx ill check oh right yeah its 12 stupid me :/

no, it is not 12 either unless you meant the

2\sqrt{3}

bit

Reply 9

TenOfThem

Original post by ChocoholicCox

oh right thx ill check oh right yeah its 12 stupid me :/

OMG this is so easy now thanks :biggrin:

good

Reply 10

Lord Frieza

Original post by ChocoholicCox

oh right thx ill check oh right yeah its 12 stupid me :/

OMG this is so easy now thanks :biggrin:

You're squaring it wrong, put the WHOLE number in a bracket and then square it because at the moment you are only squaring the roots.

Don't put it all into a calculator either

Then in the end add the two individual numbers up then root it.

(edited 10 years ago)

Reply 11

TenOfThem

Original post by arkanm

...

The OP did not need any of this

His triangle has 3 sides

2\sqrt{3}, \sqrt{13}, 5

He needed to square them all as that gives 12. 13. and 25

All he needs to show is that 12 + 13 = 25 therefore Pythagoras is satisfied and the triangle is right angled

Reply 12

TenOfThem

Original post by arkanm

I was just trying to explain why the hypotenuse is the greatest side. It's always better knowing where the maths you're doing actually comes from. :smile:

Whilst I agree that understanding is important

On a forum like this it is very important to consider the ability and current level of understanding of the OP