document.write( "Question 224547: Pleas help me solve...
\n" ); document.write( "Find an equation of the line containing the given pair of points. (4,2), (12,6)
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Algebra.Com's Answer #167876 by drj(1380)\"\" \"About 
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Find an equation of the line containing the given pair of points. (4,2), (12,6)\r
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\n" ); document.write( "\n" ); document.write( "Step 1. We will put the equation of the line in slope-intercept form given as y=mx+b where m is the slope and b is the y-intercept when x=0 or at point (0,b).\r
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\n" ); document.write( "\n" ); document.write( "Step 2. 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=2, x2=12 and y2=6 (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 3. Substituting the above values in the slope equation gives\r
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\n" ); document.write( "\n" ); document.write( "\"m=%286-2%29%2F%2812-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=4%2F8=1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Step 4. The slope is calculated as \"1%2F2\" or \"m=1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Step 5. Now use the slope equation of Step 2 and choose one of the given points. I'll choose point (4,2). Letting y=y2 and x=x2 and substituting \"m=1%2F2\" 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( "\"+1%2F2=%28y-2%29%2F%28x-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "Step 6. 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( "\"+%28x-4%29%2F2=%28x-4%29%28y-2%29%2F%28x-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"+%28x-4%29%2F2=y-2\"\r
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\n" ); document.write( "\n" ); document.write( "Step 7. Now simplify and put the above equation into slope-intercept form.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2F2-4%2F2=y-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2F2-2=y-2\"\r
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\n" ); document.write( "\n" ); document.write( "Add 2 from both sides of the equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%2F2-2%2B2=y-2%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2F2=y\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%2F2\" This is in slope-intercept form where the slope m=1/2 and y-intercept b=0\r
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\n" ); document.write( "\n" ); document.write( "Step 8. See if the other point (12,6) or x=12 and y=6 satisfies this equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"6=12%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"6=6\" So the point (12,6) 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( "Step 9. ANSWER: The equation of the line is \"y=x%2F2\"\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( "\"-x%2B2y=0\"\r
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\n" ); document.write( "\n" ); document.write( "See graph below to check the above steps.\r
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Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation \"-1+x+%2B+2+y+=+0\" describes a sloping line. For any
\n" ); document.write( " equation ax+by+c = 0, slope is \"-a%2Fb+=+--1%2F2\".
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. 0/-1 = 0.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is 0/2 = 0.
  • Slope is --1/2 = 0.5.
  • Equation in slope-intercept form: y=0.5*x+0.
\"graph%28+500%2C+500%2C+0-8%2C+0%2B8%2C+0-8%2C+0%2B8%2C+0.5%2Ax%2B0+%29+\"\n" ); document.write( "

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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( "\n" ); document.write( "For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r
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\n" ); document.write( "\n" ); document.write( "Good luck in your studies!\r
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\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
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