document.write( "Question 1001325: what is the focus diretrix and and axis of symmetry for -x^2=48y
\n" ); document.write( "i think the focus is (0,12) but im not sure \n" ); document.write( "
Algebra.Com's Answer #618560 by Boreal(15235)\"\" \"About 
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48y= -x^2
\n" ); document.write( "y= -(1/48)x^2. This is a parabola that opens downward, is wide due to the small coefficient of x, and is symmetrical around the y-axis. The focus will be negative, the directrix positive.
\n" ); document.write( "(y-0)^2= (-1/48)(x-0)^2
\n" ); document.write( "4p(y-k)=(x-h)^2
\n" ); document.write( "y^2=(-1/48)(x-0)^2
\n" ); document.write( "-48y^2=(x-0)^2
\n" ); document.write( "4p=-48
\n" ); document.write( "p=-12
\n" ); document.write( "The focus is 12 units below the vertex, which is at (0,0). That would be at (0,-12)
\n" ); document.write( "The axis of symmetry is the y-axis, or x=0.
\n" ); document.write( "The directrix is 12 units above the vertex or y=12
\n" ); document.write( "\"graph%28300%2C200%2C-40%2C40%2C-20%2C20%2C%28-1%2F48%29x%5E2%2C12%29\"
\n" ); document.write( "Check a point. At x=6, y=-36/48 or -3/4. The distance of the point from the directrix is 12.75 units.
\n" ); document.write( "The distance of that point (6,-0.75) from the focus is sqrt (6^2+11.25^2)=sqrt(162.5625)=12.75 units
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