document.write( "Question 1180174: This question is from the CEMC math competition from last year. \r
\n" ); document.write( "\n" ); document.write( "The parabola y = -x^2 has vertex labelled P and intersects the x-axis at the points labelled A and B. The parabola translated from it's original position so that its vertex moves along the line y = x+4 to the point Q. In this new position, the parabola intersects the x-axis at the points labelled B and C. What are the coordinates of C?\r
\n" ); document.write( "\n" ); document.write( "Please view diagram here: \r
\n" ); document.write( "\n" ); document.write( "https://docs.google.com/document/d/1Cl3HrcoR6jibNzxfDTIilS3imSplLY8nQUU0OpU9vLA/edit?usp=sharing
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Algebra.Com's Answer #809816 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!

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\n" ); document.write( "\n" ); document.write( " For the original parabola \"y=-x%5E2%2B+4\", the vertex is P(\"0\",\"4\") and the x-intercepts are A(\"-2\",\"0\") and B(\"2\",\"0\").\r
\n" ); document.write( "\n" ); document.write( "Let the vertex of the translated parabola be Q(\"q\", \"p\"). \r
\n" ); document.write( "\n" ); document.write( "Since the new parabola is a translation of the original, the equation of this new parabola is \r
\n" ); document.write( "\n" ); document.write( "\"y=-%28x-q%29%5E2%2Bp\"\r
\n" ); document.write( "\n" ); document.write( "Since Q lies on the line \"y=x%2B+4\", we have \"p=q%2B+4\" and the equation of the newparabola is
\n" ); document.write( "\"y=-%28x-q%29%5E2%2Bq%2B+4\"\r
\n" ); document.write( "\n" ); document.write( "Since B( \"2\",\"0\") lies on the new parabola, we can substitute (\"2\",\"0\") into this equation:\r
\n" ); document.write( "\n" ); document.write( "\"0+=-%282-q%29%5E2%2Bq%2B+4\"
\n" ); document.write( "\"0+=-%28q%5E2-4q%2B+4%29+%2Bq%2B+4\"
\n" ); document.write( "\"0+=-q%5E2%2B+4q-4+%2Bq%2B+4\"
\n" ); document.write( "\"0+=-q%5E2%2B+5q\"
\n" ); document.write( "\"0+=-q%28q-5%29\"\r
\n" ); document.write( "\n" ); document.write( "Therefore, \"q=+0\" or \"q=+5\". \r
\n" ); document.write( "\n" ); document.write( "The value \"q=+0\" corresponds to point P(\"0\",\"4\") in theoriginal parabola. Therefore, \"q=+5\" and the vertex of the new parabola is Q(\"5\",\"9\") and the equation of this parabola is\r
\n" ); document.write( "\n" ); document.write( "\"y=-%28x-5%29%5E2%2B+9\"\r
\n" ); document.write( "\n" ); document.write( "Since C is an \"x\"-intercept of this parabola, to determine C set \"y=+0\" in the equation for the parabola and solve for \"x\":\r
\n" ); document.write( "\n" ); document.write( "\"0+=-%28x-5%29%5E2%2B+9\"
\n" ); document.write( "\"%28x-5%29%5E2=+9\"
\n" ); document.write( "\"x-5\" = ± \"3\"
\n" ); document.write( "\"x=+8\" or \"x=2\",\r
\n" ); document.write( "\n" ); document.write( "\"x=2\" corresponds to point B, and the value \"x=+8\" corresponds topointC. \r
\n" ); document.write( "\n" ); document.write( "Therefore, the coordinates of C are (\"8\",\"0\").\r
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