document.write( "Question 148000: Find the vertex and intercepts for this parabola:\r
\n" ); document.write( "\n" ); document.write( "g(x) = x^2 + x - 6\r
\n" ); document.write( "\n" ); document.write( "This is how I have worked it:
\n" ); document.write( "a = 1, b = 1, c = -6\r
\n" ); document.write( "\n" ); document.write( "x = -b/2a
\n" ); document.write( "x = -1/[2(1)] = -1/2\r
\n" ); document.write( "\n" ); document.write( "g(-1/2) = (-1/2)^2 + (-1/2) - 6
\n" ); document.write( "= 25/2\r
\n" ); document.write( "\n" ); document.write( "So, the vertex is (-1/2, 25/2)\r
\n" ); document.write( "\n" ); document.write( "Am I correct so far?\r
\n" ); document.write( "\n" ); document.write( "How do I verify that I am correct? What should my next step be?\r
\n" ); document.write( "\n" ); document.write( "I appreciate your help very much! Thank you!
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Algebra.Com's Answer #108389 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Vertex:\r
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\n" ); document.write( "\n" ); document.write( "In order to find the vertex, we first need to find the x-coordinate of the vertex.\r
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\n" ); document.write( "\n" ); document.write( "To find the x-coordinate of the vertex, use this formula: \"x=%28-b%29%2F%282a%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-b%29%2F%282a%29\" Start with the given formula.\r
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\n" ); document.write( "\n" ); document.write( "From \"y=x%5E2%2Bx-6\", we can see that \"a=1\", \"b=1\", and \"c=-6\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-%281%29%29%2F%282%281%29%29\" Plug in \"a=1\" and \"b=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-1%29%2F%282%29\" Multiply 2 and \"1\" to get \"2\".\r
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\n" ); document.write( "\n" ); document.write( "So the x-coordinate of the vertex is \"x=-1%2F2\". Note: this means that the axis of symmetry is also \"x=-1%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "Now that we know the x-coordinate of the vertex, we can use it to find the y-coordinate of the vertex.\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2%2Bx-6\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29%5E2-1%2F2-6\" Plug in \"x=-1%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29%5E2-1%2F2-6\" Plug in \"x=-1%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2F4-1%2F2-6\" Square \"-1%2F2\" to get \"1%2F4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-25%2F4\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the vertex is \r
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\n" ); document.write( "\n" ); document.write( "note: you can verify this with a calculator. You can use the \"min/max\" feature. \r
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\n" ); document.write( "\n" ); document.write( "Intercepts:\r
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\n" ); document.write( "\n" ); document.write( "x-intercept:\r
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\n" ); document.write( "\n" ); document.write( "To find the x-intercept, plug in \"y=0\" and solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2%2Bx-6\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"0=x%5E2%2Bx-6\" Plug in \"y=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%28x-2%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
\n" ); document.write( "\n" ); document.write( "\"x%2B3=0\" or \"x-2=0\" \r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" or \"x=2\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "So the x-intercepts are (-3,0) and (2,0)\r
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\n" ); document.write( "\n" ); document.write( "y-intercept:\r
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\n" ); document.write( "\n" ); document.write( "To find the y-intercept, plug in \"x=0\" and simplify\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2%2Bx-6\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=0%5E2%2B0-6\" Plug in \"x=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-6\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the y-intercept is (0,-6) \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=x%5E2%2Bx-6\" we can visually verify our answers.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C0%2C+x%5E2%2Bx-6%29+\" Graph of \"y=x%5E2%2Bx-6\"
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