document.write( "Question 471502: find the coordinates of the points of intersection of the parabola y=x2 and the line y=x+2 \n" ); document.write( "
Algebra.Com's Answer #323376 by Edwin McCravy(20054)\"\" \"About 
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find the coordinates of the points of intersection of the parabola y=x2 and the line y=x+2
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document.write( "Here is the graph of the parabola y=x²\r\n" );
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document.write( "Here is the graph of the line y=x+2:\r\n" );
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document.write( "Now we'll find the coordinates of those two points where\r\n" );
document.write( "they intersect:\r\n" );
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document.write( "\"system%28y=x%5E2%2Cy=x%2B2%29\"\r\n" );
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document.write( "Substitute \"x%5E2\" for y in the second equation:\r\n" );
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document.write( "\"x%5E2=x%2B2\"\r\n" );
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document.write( "Get 0 on the right:\r\n" );
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document.write( "\"x%5E2-x-2=0\"\r\n" );
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document.write( "Factor the left side:\r\n" );
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document.write( "\"%28x-2%29%28x%2B1%29=0\"\r\n" );
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document.write( "Use the zero factor principle:\r\n" );
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document.write( "x-2 = 0     x+1 = 0\r\n" );
document.write( "  x = 2       x = -1\r\n" );
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document.write( "Now we have to find the y coordinates to go\r\n" );
document.write( "with each of these x-coordinates:\r\n" );
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document.write( "Find the y-coordinate that goes with x = 2\r\n" );
document.write( "by substituting in\r\n" );
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document.write( "y = x+2\r\n" );
document.write( "y = 2+2\r\n" );
document.write( "y = 4\r\n" );
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document.write( "So one point is (x,y) = (2,4)\r\n" );
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document.write( "Find the y-coordinate that goes with x = -1\r\n" );
document.write( "by substituting in\r\n" );
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document.write( "y = x+2\r\n" );
document.write( "y = -1+2\r\n" );
document.write( "y = 1\r\n" );
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document.write( "So the other point is (x,y) = (-1,1)\r\n" );
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document.write( "And if we look at the graph we see that it checks\r\n" );
document.write( "with those:\r\n" );
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document.write( "Edwin
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