document.write( "Question 706005: how can i find the focus/foci and vertex/vertices\r
\n" ); document.write( "\n" ); document.write( "x^2-4y^2-2x+16y=20\r
\n" ); document.write( "\n" ); document.write( "this is how far i have gotten, but i am not sure if it is right so far\r
\n" ); document.write( "\n" ); document.write( "x^2-4y^2-2x+16y=20
\n" ); document.write( "(x^2-2x+1)-4(y^2+4y+4)=20+1+4
\n" ); document.write( "(x-1)^2/25-4(y+4)^2/25=25/25
\n" ); document.write( "(x-1)^2/25-4(y+4)^2/25=1\r
\n" ); document.write( "\n" ); document.write( "please help. thank you.
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Algebra.Com's Answer #434927 by lwsshak3(11628)\"\" \"About 
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how can i find the focus/foci and vertex/vertices
\n" ); document.write( "x^2-4y^2-2x+16y=20
\n" ); document.write( "complete the square:
\n" ); document.write( "x^2-2x-4y^2+16y=20
\n" ); document.write( "(x^2-2x+1)-4(y^2-4y+4)=20+1-16
\n" ); document.write( "(x-1)^2-4(y-2)^2=5
\n" ); document.write( "\"%28x-1%29%5E2%2F5-4%28y-2%29%5E2%2F%285%2F4%29=1\"
\n" ); document.write( "This is an equation of a hyperbola with horizontal transverse axis.
\n" ); document.write( "Its standard form: \"%28x-h%29%5E2%2Fa%5E2-%28y-k%29%5E2%2Fb%5E2=1\", (h,k)=(x,y) coordinates of the center.
\n" ); document.write( "For given equation:
\n" ); document.write( "Center: (1,2)
\n" ); document.write( "a=5
\n" ); document.write( "a^2=25
\n" ); document.write( "vertices: (1±a,2)=(1±5,2)=(-4,2) and (6,2)
\n" ); document.write( "..
\n" ); document.write( "b=5/4
\n" ); document.write( "b^2=25/16
\n" ); document.write( "..
\n" ); document.write( "foci
\n" ); document.write( "c^2=a^2+b^2=25+(25/16)=425/16
\n" ); document.write( "c=√425/4≈5.15
\n" ); document.write( "foci:(1±c,2)=(1±5.15,2)=(-4.15,2) and (6.15,2)\r
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