document.write( "Question 106865This question is from textbook intermediate algebra
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\n" ); document.write( "find an equation of each line in standard form satisfying the given conditions.
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Algebra.Com's Answer #77756 by jim_thompson5910(35256)\"\" \"About 
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Solved by pluggable solver: Finding the Equation of a Line
First lets find the slope through the points (\"-3\",\"1\") and (\"2\",\"-6\")
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\n" ); document.write( " \"m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\" Start with the slope formula (note: (\"x%5B1%5D\",\"y%5B1%5D\") is the first point (\"-3\",\"1\") and (\"x%5B2%5D\",\"y%5B2%5D\") is the second point (\"2\",\"-6\"))
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\n" ); document.write( " \"m=%28-6-1%29%2F%282--3%29\" Plug in \"y%5B2%5D=-6\",\"y%5B1%5D=1\",\"x%5B2%5D=2\",\"x%5B1%5D=-3\" (these are the coordinates of given points)
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\n" ); document.write( " \"m=+-7%2F5\" Subtract the terms in the numerator \"-6-1\" to get \"-7\". Subtract the terms in the denominator \"2--3\" to get \"5\"
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\n" ); document.write( " So the slope is
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\n" ); document.write( " \"m=-7%2F5\"
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\n" ); document.write( "Now let's use the point-slope formula to find the equation of the line:
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\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 (\"x%5B1%5D\",\"y%5B1%5D\") is one of the given points
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\n" ); document.write( " So lets use the Point-Slope Formula to find the equation of the line
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\n" ); document.write( " \"y-1=%28-7%2F5%29%28x--3%29\" Plug in \"m=-7%2F5\", \"x%5B1%5D=-3\", and \"y%5B1%5D=1\" (these values are given)
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\n" ); document.write( " \"y-1=%28-7%2F5%29%28x%2B3%29\" Rewrite \"x--3\" as \"x%2B3\"
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\n" ); document.write( " \"y-1=%28-7%2F5%29x%2B%28-7%2F5%29%283%29\" Distribute \"-7%2F5\"
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\n" ); document.write( " \"y-1=%28-7%2F5%29x-21%2F5\" Multiply \"-7%2F5\" and \"3\" to get \"-21%2F5\"
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\n" ); document.write( " \"y=%28-7%2F5%29x-21%2F5%2B1\" Add \"1\" to both sides to isolate y
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\n" ); document.write( " \"y=%28-7%2F5%29x-16%2F5\" Combine like terms \"-21%2F5\" and \"1\" to get \"-16%2F5\" (note: if you need help with combining fractions, check out this solver)
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\n" ); document.write( " Answer:
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\n" ); document.write( " So the equation of the line which goes through the points (\"-3\",\"1\") and (\"2\",\"-6\") is:\"y=%28-7%2F5%29x-16%2F5\"
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\n" ); document.write( " The equation is now in \"y=mx%2Bb\" form (which is slope-intercept form) where the slope is \"m=-7%2F5\" and the y-intercept is \"b=-16%2F5\"
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\n" ); document.write( " Notice if we graph the equation \"y=%28-7%2F5%29x-16%2F5\" and plot the points (\"-3\",\"1\") and (\"2\",\"-6\"), we get this: (note: if you need help with graphing, check out this solver)
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\n" ); document.write( " Graph of \"y=%28-7%2F5%29x-16%2F5\" through the points (\"-3\",\"1\") and (\"2\",\"-6\")
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\n" ); document.write( " Notice how the two points lie on the line. This graphically verifies our answer.
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\n" ); document.write( "\n" ); document.write( "Now let's convert the slope-intercept equation into standard form\r
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Solved by pluggable solver: Converting Linear Equations in Standard form to Slope-Intercept Form (and vice versa)
Convert from slope-intercept form (y = mx+b) to standard form (Ax+By = C)


\"y+=+%28-7%2F5%29x-16%2F5\" Start with the given equation


\"5%2Ay+=+5%2A%28%28-7%2F5%29x-16%2F5%29\" Multiply both sides by the LCD 5


\"5y+=+-7x-16\" Distribute and multiply


\"5y%2B7x+=+-7x-16%2B7x\" Add 7x to both sides


\"7x%2B5y+=+-16\" Simplify


The original equation \"y+=+%28-7%2F5%29x-16%2F5\" (slope-intercept form) is equivalent to \"7x%2B5y+=+-16\" (standard form where A > 0)


The equation \"7x%2B5y+=+-16\" is in the form \"Ax%2BBy+=+C\" where \"A+=+7\", \"B+=+5\" and \"C+=+-16\"


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