document.write( "Question 243697: Hello, I need help with two problems.
\n" ); document.write( "1. Find the slope of the line containing the given pair of points. If the slope is undefined state so (5,3) and (8,-4)\r
\n" ); document.write( "\n" ); document.write( "2. Select the line that has the given slope and y intercept. slope -1/5, y intercept (0,-2)
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Algebra.Com's Answer #178497 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( "Note: is the first point . So this means that \"x%5B1%5D=5\" and \"y%5B1%5D=3\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=8\" and \"y%5B2%5D=-4\".\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=%28-4-3%29%2F%288-5%29\" Plug in \"y%5B2%5D=-4\", \"y%5B1%5D=3\", \"x%5B2%5D=8\", and \"x%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-7%29%2F%288-5%29\" Subtract \"3\" from \"-4\" to get \"-7\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-7%29%2F%283%29\" Subtract \"5\" from \"8\" to get \"3\"\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=-7%2F3\"\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 \"-1%2F5\" which goes through the point (0,-2), 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--2=%28-1%2F5%29%28x-0%29\" Plug in \"m=-1%2F5\", \"x%5B1%5D=0\", and \"y%5B1%5D=-2\" (these values are given)\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B2=%28-1%2F5%29%28x-0%29\" Rewrite \"y--2\" as \"y%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B2=%28-1%2F5%29x%2B%28-1%2F5%29%28-0%29\" Distribute \"-1%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B2=%28-1%2F5%29x%2B0\" Multiply \"-1%2F5\" and \"-0\" to get \"0\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F5%29x%2B0-2\" Subtract 2 from both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F5%29x-2\" Combine like terms\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%2F5\" which goes through the point (0,-2) is:\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F5%29x-2\" which is now in \"y=mx%2Bb\" form where the slope is \"m=-1%2F5\" and the y-intercept is \"b=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the equation \"y=%28-1%2F5%29x-2\" and plot the point (0,-2), 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%2F5%29x-2\" through the point (0,-2)\r
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\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%2F5\" and goes through the point (0,-2), this verifies our answer.
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