document.write( "Question 217928: Find the slope if it exists of the line containing the pair of points: \r
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Algebra.Com's Answer #164211 by drj(1380)\"\" \"About 
You can put this solution on YOUR website!
Find the slope if it exists of the line containing the pair of points: \r
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\n" ); document.write( "\n" ); document.write( "However, here are the steps showing you how you can check your work with one of the points.\r
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\n" ); document.write( "\n" ); document.write( "Step 1. The slope of the line m is given as\r
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\n" ); document.write( "\n" ); document.write( "\"+m=%28y2-y1%29%2F%28x2-x1%29\"\r
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\n" ); document.write( "\n" ); document.write( "where for our example is x1=4, y1=5, x2=8 and y2=-3 (think of \"slope=rise%2Frun\"). You can choose the points the other way around but be consistent with the x and y coordinates. You will get the same result.\r
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\n" ); document.write( "\n" ); document.write( "Step 2. Substituting the above values in the slope equation gives\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-3-5%29%2F%288-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-8%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Step 3. The slope is calculated as -2 or m=-2\r
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\n" ); document.write( "\n" ); document.write( "Step 4. Now use the slope equation of step 1 and choose one of the given points. I'll choose point (4,5). Letting y=y2 and x=x2 and substituting m=-2 in the slope equation given as,\r
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\n" ); document.write( "\n" ); document.write( "\"+m=%28y2-y1%29%2F%28x2-x1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"+-2=%28y-5%29%2F%28x-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"+-2=%28y-5%29%2F%28x-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "Step 5. Multiply both sides of equation by x-4 to get rid of denomination found on the right side of the equation\r
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\n" ); document.write( "\n" ); document.write( "\"+-2%28x-4%29=%28x-4%29%28y-5%29%2F%28x-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"+-2%28x-4%29=y-5\"\r
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\n" ); document.write( "\n" ); document.write( "Step 6. Now simplify and put the above equation into slope-intercept form.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B8=y-5\"\r
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\n" ); document.write( "\n" ); document.write( "Add 5 to both sides of the equation\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B8%2B5=y-5%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B13=y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B13\" ANSWER in slope-intercept form. m=-2 and y-intercept=13\r
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\n" ); document.write( "\n" ); document.write( "Step 7. See if the other point (8,-3) or x=8 and y=-3 satisfies this equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%2B13\"\r
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\n" ); document.write( "\n" ); document.write( "\"-3=-2%2A8%2B13\" which is a true statement\r
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\n" ); document.write( "\n" ); document.write( "\"-3=-3\" So the point (8,-3) satisfies the equation and is on the line. In other words, you can use the other point to check your work.\r
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\n" ); document.write( "\n" ); document.write( "Note; above equation can be also be transform into standard form as\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2By=13\"\r
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\n" ); document.write( "\n" ); document.write( "See graph below to check the above steps and note the slope and the y-intercept at x=0\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28400%2C400%2C+-5%2C15%2C-5%2C15%2C+-2x%2B13%29\" \r
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\n" ); document.write( "\n" ); document.write( "I hope the above steps were helpful. \r
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\n" ); document.write( "And good luck in your studies!\r
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\n" ); document.write( "\n" ); document.write( "For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r
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\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
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