Complete the square in 25x^2-4y^2+100x+24y-36=0

CaliMan

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Mar 31, 2007
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25x^2-4y^2+100x+24y-36=0

Someone please help to complete the square. If someone could show me how to complete the square, then I should be able to finish the rest of it.

I've gotten to this point

(25x^2+100x)+(-4y^2+24y)=36
 
Re: Please help Complete the square in a hyperbola

Hello, CaliMan!

\(\displaystyle 25x^2\,-\,4y^2\,+\,100x\,+\,24y\,-\,36\:=\:0\)

I've gotten to this point: \(\displaystyle \:(25x^2\,+\,100x)\,+\,(-4y^2\,+\,24y)\:=\:36\)

Factor: \(\displaystyle \:25(x^2\,+\,4x\;\;\;)\,-\,4(y^2\,-\,6y\;\;\;)\:=\:36\)

Complete the square:
. . . . . \(\displaystyle 25(x^2\,+\,4x\,\)+ 4\(\displaystyle )\,-\,4(y^2\,-\,6y\,\)+ 9\(\displaystyle ) \;=\;36\,\)+ 100\(\displaystyle \,\) - 36 . **

Factor: \(\displaystyle \:25(x\,+\,2)^2\,-\,4(y\,-\,3)^2\:=\:100\)

Divide by 100: \(\displaystyle \L\:\fbox{\frac{(x\,+\,2)^2}{4}\,-\,\frac{(y\,-\,3)^2}{25}\;=\;1}\)

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** .Important

We wrote + 4 on the left side.
. . But it is multiplied by the "25" out front.
So we actually added 100 to the left side.
. . Hence, we add 100 to the right side.

We wrote + 9 on the left side.
. . But it is multiplied by the "-4" out front.
So we actually subtracted 36 from the left side.
. . Hence, we subtract 36 from the right side.

 
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