document.write( "Question 349538: Part 1:
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document.write( "Suppose you need to solve a system of equations in which one equation represents a circle and the other represents a line. How many solutions can your system have? Select ALL that are possible. \r
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document.write( "0,1,2,3,4, infinitely many\r
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document.write( "Part 2:
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document.write( "How many solutions does the following system of equations have?
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document.write( "x2+y2=64
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document.write( "x=1\r
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document.write( "0,1,2,3,4, infinitely many \n" );
document.write( "
Algebra.Com's Answer #249827 by Theo(13342)![]() ![]() You can put this solution on YOUR website! one equation represents a circle and the other equation represents a line.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you can have 0, 1, or 2 solutions.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "0 if the line and the circle never intersect \n" ); document.write( "1 if the line is tangent to the circle. \n" ); document.write( "2 if the line intersects the circle at any other angle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the line can never intersect the circle at more than 2 points.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your equation is:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x^2 + y^2 = 64 \n" ); document.write( "x = 1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this is like solving equations simultaneously to get a common solution.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if x = 1, you can substitute in the first equation to get 1 + y^2 = 64 which give you y^2 = 63 which gives you y = +/- sqrt(63).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this implies 2 solutions to this equation.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The graph of the equation of the circle should confirm this.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "To graph the equation of the circle, solve for y to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "y = +/- sqrt(64-x^2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that graph is shown below:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Draw a vertical line at x = 1 and you will see that the intersection of that vertical line and the circle is around y = +/- 7.937253933.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I drew 2 horizontal lines at y = +/- 7.937253933 so you can see that a little easier.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "when x = 0, y = +/- sqrt(64-0) = +/- sqrt(64) = +/- 8.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "That's the highest and lowest point of the circle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "when x = 1, y = +/- sqrt(64-1) = +/- sqrt(63) = +/- 7.937253933. \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "That's close to the highest point but hot exactly there (just a little below).\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Solving the 2 equations simultaneously yielded the result.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |