Mathematics
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OpenStudy (anonymous):
last problem, i swear
*x+6*-*x-5*=1 The stars mean its in a radical
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OpenStudy (anonymous):
\[\sqrt{x+6}-\sqrt{x-5}=1\]
OpenStudy (anonymous):
yes thats it
OpenStudy (anonymous):
The answer is x = 30
(I knew 30+6 is 36 and the square root of that is 6 and 30-5 is 25 and the square root of that is 5 so 6-5 = 1)
OpenStudy (anonymous):
how did you get that
OpenStudy (anonymous):
I used guess and check on this one :P. but give me a moment and I may be able to figure out how to go through the steps to prove it.
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OpenStudy (anonymous):
Sigh. This one takes a little while to type out in LaTex :P Hold on..
OpenStudy (anonymous):
sqrt ( x+6) = 1 + sqrt (x+5)
OpenStudy (anonymous):
square both sides
OpenStudy (anonymous):
x+6 = 1 + 2 sqrt (x+5) + (x+5)
OpenStudy (anonymous):
x+6 - 1 - (x+5) = 2 sqrt (x+5)
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OpenStudy (anonymous):
err
OpenStudy (anonymous):
sqrt ( x+6) = 1 + sqrt (x- 5)
OpenStudy (anonymous):
x+6 = 1 + 2 sqrt ( x - 5) + x- 5 , when you square both sides
OpenStudy (anonymous):
6 + 5-1 = 2 sqrt ( x - 5)
OpenStudy (anonymous):
10 / 2 = sqrt (x-5)
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OpenStudy (anonymous):
25 = x - 5 ,
x = 30
OpenStudy (anonymous):
THIS IS A JOKE
OpenStudy (anonymous):
anwar, we are trying to do the proof
OpenStudy (anonymous):
in my post
OpenStudy (anonymous):
thanks for the help cantor, I was looking at conjugates for some reason
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OpenStudy (anonymous):
\[\sqrt{x+6} - \sqrt{x-5} = 1\] \[\sqrt{x-5} = \sqrt{x-6} - 1\]
squaring both sides \[x - 5 = x - 2\sqrt{x+6} - 7\]\[2\sqrt{x+6} = 12\]\[\implies x = 30\]
OpenStudy (anonymous):
Sorry, third line should have a +7.
OpenStudy (anonymous):
how are you a champion?