Pythagorean Theorem Help
well i took a test about the Pythagorean Theorem and my teacher never teached us about the Pythagorean Theorem and i just need help on this
\[a^2+b^2=c^2\] is the theorem. It's used to find the diagonal of the gright triangle. |dw:1389375102485:dw| a and b are the legs of the triangle, b is the hypotenuse.
I meant right triangle not gright, sorry.
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So FOR EXAMPLE: |dw:1389375163460:dw| use the theorem, plug in numbers.\[6^2+8^2=c^2\]Solve for c.\[36+64=c^2\]\[100=c^2~~~~~~~->~~~~~c=10\]
oops If X = 3 units and Y = 12 units, what is the length of Z?|dw:1389375248416:dw|
thats the triangle
\[\sqrt{15} \sqrt{153} \sqrt{163}\] 153
\[3^3+12^2=Z^2\]
\[Z=?\]
yes
No, Z doesn't equal "yes", it equals a number, which you should calculate :-) \[3^2=3*3=\]\[9^2=9*9=\]Add those two numbers together, what do you get?
3x3=9 and 9x9=81
sorry 9+9=18 and 3+3= 6
sorry, that should have been \[12^2 = 12*12 = \]no idea where 9 came from!
LoL
12-3=9, that must be it :-)
12-3=9 yes its correct
but back to the real problem, what is \[12^2= 12*12 =\]
so is it 12+12 or 12x12
\(12*12\) is multiplication
ok 12x12=144
right, so by Pythagorean theorem, \[Z^2 = X^2+Y^2\]and we have determined that \[X^2=3*3=9\]and\[Y^2=12*12=144\]
what does \(Z^2=\) what about \(Z=\) (which is what the problem requests we find)
hmm z must be 144 but i might be rong
No, \[Z^2 = X^2+Y^2 = 9+144 = \]
153
Right. So if \[Z^2=153\]what does \[Z=\]
153 or
am i rong?
Well, if Z*Z = 153, can Z=153?
I haven't made a close study of the number 153, but I think the answer is no :-)
so we might have to divide
we need the square root of 153, or \(\sqrt{153}\) the square root of some number is defined as another number, which when multiplied by itself, gives you the first number. For example, the square root of 4 is 2, because 2*2 = 4.
\[\sqrt{x}*\sqrt{x} = x\] \[\sqrt{153}*\sqrt{153} = 153\] So if \[Z^2=153\]then \[Z=\sqrt{153}\]
ok so thats the answer Z\[\sqrt{153}\]
notice that there was a "trap" answer of 153 in your answer choices, put there to catch careless students who just added X^2 and Y^2 and forgot that that gives them Z^2, not Z
and \[\sqrt{15}\]was probably intended to catch people who forgot to square X and Y before adding them...
there fore thats not the answer?
the correct answer is the one we found: \[Z = \sqrt{153}\]
ok so it was but you where giving me a explanation of the answer right?
2 of the other answers are answers you get if you make various predictable mistakes. I'm not sure how you might get \[Z = \sqrt{163}\]but I'm sure there's some student who could manage to do it :-) Yes, I wanted you to see the importance of working carefully and not just grabbing the first answer that appears to have a number you got...
right right and i live teachers like you :) how many can you do?
let's do another one!
:D ok
If X = 10 cm and Y = 10 cm, what is the length of Z? |dw:1389377822260:dw|
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