document.write( "Question 1048919: For the parabola whose equation is​ given, determine whether it opens upward or​ downward, find the​ vertex, and find the​ x- and​ y-intercepts. Then graph the parabola.
\n" ); document.write( "​f(x)=x squared minus 2 x minus 48
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Algebra.Com's Answer #664508 by advanced_Learner(501)\"\" \"About 
You can put this solution on YOUR website!
given function
\n" ); document.write( "\"y\"=\"x%5E2-2x-48\"
\n" ); document.write( "find\r
\n" ); document.write( "\n" ); document.write( "a.opens upward or downward?
\n" ); document.write( "b.vertex
\n" ); document.write( "c.x intercepts?
\n" ); document.write( "d.y-intercepts.
\n" ); document.write( "e.graph\r
\n" ); document.write( "\n" ); document.write( "Solution\r
\n" ); document.write( "\n" ); document.write( "\"a\"\r
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\n" ); document.write( "\n" ); document.write( "\"y\"=\"x%5E2-2x-48\"\r
\n" ); document.write( "\n" ); document.write( "a=\"1\",b=\"-2\",c=\"-48\"\r
\n" ); document.write( "\n" ); document.write( " therefore,it opens upward since a=\"1\" is positive.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"b\".\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"x%5E2-2x-48\"\r
\n" ); document.write( "\n" ); document.write( "vertex x part =\"-b%2F2a\"\r
\n" ); document.write( "\n" ); document.write( "vertex=\"2%2F2\"\r
\n" ); document.write( "\n" ); document.write( "vertex=\"1\"\r
\n" ); document.write( "\n" ); document.write( "vertex y part =\"1-2-48\" \r
\n" ); document.write( "\n" ); document.write( "vertex y part=\"-49\"\r
\n" ); document.write( "\n" ); document.write( "another solution by completing the square.\r
\n" ); document.write( "\n" ); document.write( "\"48\"=\"x%5E2-2x\"\r
\n" ); document.write( "\n" ); document.write( "\"48%2B1\"=\"x%5E2-2x%2B1\"\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"%28x-1%29%5E2\"-\"49\" so now the function is written as vertex form\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"a\"\"%28x-h%29%5E2\"+\"k\"\r
\n" ); document.write( "\n" ); document.write( "so clearly\r
\n" ); document.write( "\n" ); document.write( "\"h\"=\"1\"
\n" ); document.write( "\"k\"=\"-49\"\r
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\n" ); document.write( "\n" ); document.write( "\"c\".x intercepts\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"x%5E2-2x-48\"\r
\n" ); document.write( "\n" ); document.write( "set y=\"0\" and solve for x\r
\n" ); document.write( "\n" ); document.write( "\"0\"=\"x%5E2-2x-48\"\r
\n" ); document.write( "\n" ); document.write( "\"0\"=\"%28x%2B6%29%28x-8%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x\"=\"8\" or \"x\"=\"-6\"\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-2x%2B-48+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-2%29%5E2-4%2A1%2A-48=196\".
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\n" ); document.write( " Discriminant d=196 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--2%2B-sqrt%28+196+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"x%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+196+%29%29%2F2%5C1+=+8\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-2%29-sqrt%28+196+%29%29%2F2%5C1+=+-6\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"1x%5E2%2B-2x%2B-48\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-2x%2B-48+=+1%28x-8%29%2A%28x--6%29\"
\n" ); document.write( " Again, the answer is: 8, -6.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-2%2Ax%2B-48+%29\"

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\n" ); document.write( "\n" ); document.write( "\"d\".y intercepts \r
\n" ); document.write( "\n" ); document.write( "set x=\"0\" and solve for \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"x%5E2-2x-48\"\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"0-0-48\"\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"-48\"\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"e\".graph\r
\n" ); document.write( "\n" ); document.write( "\"y\"=\"x%5E2-2x-48\"\r
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-2x%2B-48+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
\n" ); document.write( "
\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-2%29%5E2-4%2A1%2A-48=196\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=196 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--2%2B-sqrt%28+196+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"x%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+196+%29%29%2F2%5C1+=+8\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-2%29-sqrt%28+196+%29%29%2F2%5C1+=+-6\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"1x%5E2%2B-2x%2B-48\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-2x%2B-48+=+1%28x-8%29%2A%28x--6%29\"
\n" ); document.write( " Again, the answer is: 8, -6.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-2%2Ax%2B-48+%29\"
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