#algebra ordered pair

33 messages · Page 1 of 1 (latest)

white salmon
blissful plinth
# white salmon

is this asking you to find the number of ordered pairs in Q^2, or...?

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or Z^2 more likely

white salmon
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I’m not getting your question

blissful plinth
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like

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there are infinitely many solutions

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well, maybe that's the answer which i just spoiled for you

white salmon
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Oh I forgot to write that they must be integers

wheat wedge
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Hm, looks interesting.

blissful plinth
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alr

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so you can rewrite as

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x^2 + (x-y)^2 = 289

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that might help you

white salmon
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Ye I got that eqn but it got really complicated as I was getting 4 values of X and four values of X-y

blissful plinth
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hm
what values did you get

wheat wedge
# white salmon

We have:
x^2 + (x^2 - 2xy + y^2) = 289
x^2 + (x - y)^2 = 289
Now, note that 289^2 = 17^2 = 8^2 + 15^2. So, you can make 8 systems of equations.

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Actually, hold on, might be more than 8.

blissful plinth
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i think it is

white salmon
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X= +-64 and X=+-225 and X-y = +64 and X-y =+-225

blissful plinth
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and X = 0

wheat wedge
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(x, x - y) can be...
(±17, 0)
(0, ±17)
(±8, ±15)
(±15, ±8)
(±8, ∓15)
(±15, ∓8)
So, 12 systems.

white salmon
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But the ordered pair must be in the form of (X,y)

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So there probably more

wheat wedge
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So, for each pair (x, x - y) there's a unique pair (x, y).

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And, considering that both will be integers, all 12 systems should give an integer solution.

white salmon
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hmm I see

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wish I paid more attention to these points in class .-.

wheat wedge
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No worries! You just need some practice.

white salmon
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yea anyways thanks for your help

wheat wedge
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You're welcome!