document.write( "Question 175495: Write a linear equation in the form y=mx+b givien the following information.
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Algebra.Com's Answer #130570 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "If you want to find the equation of line with a given a slope of \"2%2F3\" which goes through the point (\"12\",\"3\"), you can simply use the point-slope formula to find the equation:\r
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\n" ); document.write( "\n" ); document.write( "---Point-Slope Formula---
\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" where \"m\" is the slope, and is the given point\r
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\n" ); document.write( "\n" ); document.write( "So lets use the Point-Slope Formula to find the equation of the line\r
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\n" ); document.write( "\n" ); document.write( "\"y-3=%282%2F3%29%28x-12%29\" Plug in \"m=2%2F3\", \"x%5B1%5D=12\", and \"y%5B1%5D=3\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y-3=%282%2F3%29x%2B%282%2F3%29%28-12%29\" Distribute \"2%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-3=%282%2F3%29x-8\" Multiply \"2%2F3\" and \"-12\" to get \"-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%282%2F3%29x-8%2B3\" Add 3 to both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=%282%2F3%29x-5\" Combine like terms \"-8\" and \"3\" to get \"-5\" \r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line with a slope of \"2%2F3\" which goes through the point (\"12\",\"3\") is:\r
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\n" ); document.write( "\n" ); document.write( "\"y=%282%2F3%29x-5\" which is now in \"y=mx%2Bb\" form where the slope is \"m=2%2F3\" and the y-intercept is \"b=-5\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=%282%2F3%29x-5\" and plot the point (\"12\",\"3\"), we get (note: if you need help with graphing, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=%282%2F3%29x-5\" through the point (\"12\",\"3\")\r
\n" ); document.write( "\n" ); document.write( "and we can see that the point lies on the line. Since we know the equation has a slope of \"2%2F3\" and goes through the point (\"12\",\"3\"), this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "c)\r
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\n" ); document.write( "\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=%28-1-5%29%2F%28-3-5%29\" Plug in \"y%5B2%5D=-1\", \"y%5B1%5D=5\", \"x%5B2%5D=-3\", and \"x%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-6%29%2F%28-3-5%29\" Subtract \"5\" from \"-1\" to get \"-6\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-6%29%2F%28-8%29\" Subtract \"5\" from \"-3\" to get \"-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=3%2F4\" 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=3%2F4\"\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=%283%2F4%29%28x-5%29\" Plug in \"m=3%2F4\", \"x%5B1%5D=5\", and \"y%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=%283%2F4%29x%2B%283%2F4%29%28-5%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=%283%2F4%29x-15%2F4\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F4%29x-15%2F4%2B5\" Add 5 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F4%29x%2B5%2F4\" Combine like terms. note: If you need help with fractions, check out this
solver.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F4%29x%2B5%2F4\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=%283%2F4%29x%2B5%2F4\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=%283%2F4%29x%2B5%2F4\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=%283%2F4%29x%2B5%2F4\" through the points and \r
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