document.write( "Question 1166292: In 1 and 2, do the following:
\n" );
document.write( " a) Write the equation of the parabola in standard form.
\n" );
document.write( " b) Find the vertex, focus, equation of the directrix and axis of symmetry of the parabola.
\n" );
document.write( "1. x^2-6x-5y-1=0
\n" );
document.write( "2. y^2-2y+3x-8=0\r
\n" );
document.write( "\n" );
document.write( "In 3 and 4, find an equation of the parabola that satisfies the given conditions. Express the answer in standard and general forms.
\n" );
document.write( "3. Vertex at V(-4,3),directrix at y=5.
\n" );
document.write( "4. Focus at F(-1,-5),directrix at x=-2.\r
\n" );
document.write( "\n" );
document.write( "5. Each cable of a suspension bridge is in the shape of a parabola and is supported by two towers at each end (refer to the figure below). The shape of the cable is modeled by the equation
\n" );
document.write( " x^2=200y
\n" );
document.write( "where x and y are measured in meters. Find the coordinates of the focus.\r
\n" );
document.write( "\n" );
document.write( " \n" );
document.write( "
Algebra.Com's Answer #790795 by greenestamps(13200)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "One problem per post!!! \n" ); document.write( "Here is all you need to work these problems yourself.... \n" ); document.write( "Vertex form of equation of a parabola that opens up or down: \n" ); document.write( " \n" ); document.write( "or \n" ); document.write( " \n" ); document.write( "Vertex form of equation of a parabola that opens right or left: \n" ); document.write( " \n" ); document.write( "or \n" ); document.write( " \n" ); document.write( "In both formulas, the vertex is (h,k), and p is the directed distance from the directrix to the vertex and from the vertex to the focus. \n" ); document.write( "Here is a problem like your problems 1 and 2.... \n" ); document.write( " \n" ); document.write( "Complete the square in x and put the equation in vertex form. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "That is vertex form: h=2; k=4; 4p=4 so p=1. \n" ); document.write( "The vertex is (h,k) = (2,4). \n" ); document.write( "p=1, so the directed distance from the directrix to the vertex is 1, and the directed distance from the vertex to the focus is 1. That makes the directrix y=3 and the focus (2,5). \n" ); document.write( "Your problem 5 is solved in a similar fashion. \n" ); document.write( "For problems 3 and 4, use the definitions of (h,k) and p to write the equations. \n" ); document.write( " \n" ); document.write( " |