document.write( "Question 130249: If the slope is negative one-fourth (-1/4) and passes through the point (4,4), what's the equation in the form y=mx+b?\r
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Algebra.Com's Answer #95129 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1\r
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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 \"-1%2F4\" which goes through the point (\"4\",\"4\"), 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-4=%28-1%2F4%29%28x-4%29\" Plug in \"m=-1%2F4\", \"x%5B1%5D=4\", and \"y%5B1%5D=4\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=%28-1%2F4%29x%2B%28-1%2F4%29%28-4%29\" Distribute \"-1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=%28-1%2F4%29x%2B1\" Multiply \"-1%2F4\" and \"-4\" to get \"1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F4%29x%2B1%2B4\" Add 4 to both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F4%29x%2B5\" Combine like terms \"1\" and \"4\" to get \"5\" \r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line with a slope of \"-1%2F4\" which goes through the point (\"4\",\"4\") is:\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F4%29x%2B5\" which is now in \"y=mx%2Bb\" form where the slope is \"m=-1%2F4\" 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=%28-1%2F4%29x%2B5\" and plot the point (\"4\",\"4\"), 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=%28-1%2F4%29x%2B5\" through the point (\"4\",\"4\")\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 \"-1%2F4\" and goes through the point (\"4\",\"4\"), this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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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 \"4\" which goes through the point (\"0\",\"12\"), 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-12=%284%29%28x-0%29\" Plug in \"m=4\", \"x%5B1%5D=0\", and \"y%5B1%5D=12\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y-12=4x%2B%284%29%28-0%29\" Distribute \"4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-12=4x%2B0\" Multiply \"4\" and \"-0\" to get \"0\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=4x%2B0%2B12\" Add 12 to both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=4x%2B12\" Combine like terms \"0\" and \"12\" to get \"12\" \r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line with a slope of \"4\" which goes through the point (\"0\",\"12\") is:\r
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\n" ); document.write( "\n" ); document.write( "\"y=4x%2B12\" which is now in \"y=mx%2Bb\" form where the slope is \"m=4\" and the y-intercept is \"b=12\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=4x%2B12\" and plot the point (\"0\",\"12\"), 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=4x%2B12\" through the point (\"0\",\"12\")\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 \"4\" and goes through the point (\"0\",\"12\"), this verifies our answer.\r
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