document.write( "Question 171404: Write the equation of the line through (2,5) and (-1,11) in the slope intercept form (y=mx+b) \n" ); document.write( "
Algebra.Com's Answer #126544 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "First let's find the slope of the line through the points and \r
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\n" ); document.write( "\n" ); document.write( "\"m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\" Start with the slope formula.\r
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\n" ); document.write( "\n" ); document.write( "\"m=%2811-5%29%2F%28-1-2%29\" Plug in \"y%5B2%5D=11\", \"y%5B1%5D=5\", \"x%5B2%5D=-1\", and \"x%5B1%5D=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%286%29%2F%28-1-2%29\" Subtract \"5\" from \"11\" to get \"6\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%286%29%2F%28-3%29\" Subtract \"2\" from \"-1\" to get \"-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-2\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the slope of the line that goes through the points and is \"m=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the point slope formula:\r
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\n" ); document.write( "\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" Start with the point slope formula\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=-2%28x-2%29\" Plug in \"m=-2\", \"x%5B1%5D=2\", and \"y%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=-2x%2B-2%28-2%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=-2x%2B4\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B4%2B5\" Add 5 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B9\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B9\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=-2x%2B9\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=-2x%2B9\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=-2x%2B9\" through the points and \r
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