document.write( "Question 357156: What is the x, y values for the eqautions y=-2x+7, and y=x^2-4x, I need to find the x, y values then plott onto a graph. \r
\n" ); document.write( "\n" ); document.write( "Donetta McCormick \n" ); document.write( "
Algebra.Com's Answer #255043 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"y=-2x%2B7\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-4x=-2x%2B7\" Plug in \"y=x%5E2-4x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-4x%2B2x-7=0\" Get every term to the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x-7=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2-2x-7\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=-2\", and \"C=-7\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"x\":\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-7%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=-2\", and \"C=-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%281%29%28-7%29+%29%29%2F%282%281%29%29\" Negate \"-2\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4-4%281%29%28-7%29+%29%29%2F%282%281%29%29\" Square \"-2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4--28+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-7%29\" to get \"-28\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4%2B28+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%284--28%29\" as \"sqrt%284%2B28%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+32+%29%29%2F%282%281%29%29\" Add \"4\" to \"28\" to get \"32\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+32+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+4%2Asqrt%282%29%29%2F%282%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282%29%2F%282%29+%2B-+%284%2Asqrt%282%29%29%2F%282%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1+%2B-+2%2Asqrt%282%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1%2B2%2Asqrt%282%29\" or \"x+=+1-2%2Asqrt%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+1%2B2%2Asqrt%282%29\" or \"x+=+1-2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's find the corresponding y values.\r
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\n" ); document.write( "\n" ); document.write( "Let's find the value of y when \"x+=+1%2B2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B7\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2%281%2B2%2Asqrt%282%29%29%2B7\" Plug in \"x+=+1%2B2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2-4%2Asqrt%282%29%2B7\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"y=5-4%2Asqrt%282%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x+=+1%2B2%2Asqrt%282%29\", \"y=5-4%2Asqrt%282%29\" which gives us the ordered pair \r
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\n" ); document.write( "\n" ); document.write( "Now let's find the value of y when \"x+=+1-2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B7\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2%281-2%2Asqrt%282%29%29%2B7\" Plug in \"x+=+1-2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2%2B4%2Asqrt%282%29%2B7\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"y=5%2B4%2Asqrt%282%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x+=+1-2%2Asqrt%282%29\", \"y=5%2B4%2Asqrt%282%29\" which gives us the ordered pair \n" ); document.write( "
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