document.write( "Question 397332: Find the intersection of the line through the points (7,10) and (4,2) with the line y=x. The point of intersection is (A,B) where A=? and B=? \n" ); document.write( "
Algebra.Com's Answer #281640 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
given:\r
\n" ); document.write( "\n" ); document.write( "\"x1=+7\"
\n" ); document.write( "\"+y1=+10\"
\n" ); document.write( "\"+x2=+4+\"
\n" ); document.write( "\"y2=+2\"\r
\n" ); document.write( "\n" ); document.write( "solpe \"m=+%28y2-y1%29%2F%28x2-x1%29\"\r
\n" ); document.write( "\n" ); document.write( "= \"%282-%2810%29%29%2F%284-%287%29%29\"\r
\n" ); document.write( "\n" ); document.write( "= \"%282-10%29%2F%284-7%29\"\r
\n" ); document.write( "\n" ); document.write( "= \"-8%2F-3\" \r
\n" ); document.write( "\n" ); document.write( "=\"8%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+%28y1-m%2Ax1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=10-%28%28-8%29%2F%28-3%29%29%287%29+=+10-+%2856%2F3%29+=+-26%2F3\"\r
\n" ); document.write( "\n" ); document.write( "Equation: \"y=+mx+%2Bb+\", \"m+=+slope\"\r
\n" ); document.write( "\n" ); document.write( "Equation of the line is :\r
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\n" ); document.write( "\n" ); document.write( " \"y+=+%288%2F3%29+x+-26%2F3\" ----(1)\r
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\n" ); document.write( "\n" ); document.write( "To find the \"intersection\" of this line with \"y=x\", replace\"+y\" with \"x\" in (1)\r
\n" ); document.write( "\n" ); document.write( "\"x+=+%288%2F3%29x+-+26%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"3x=8x-26\"\r
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\n" ); document.write( "\n" ); document.write( "\"-5x=-26\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=26%2F5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%288%2F3%29%2826%2F5%29-26%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=208%2F15+-26%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=78%2F15+=+26%2F5=5%281%2F5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"A=5%281%2F5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"B=5%281%2F5%29\"\r
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\n" ); document.write( "\n" ); document.write( "graph:\r
\n" ); document.write( "\n" ); document.write( "in standard form you have:\r
\n" ); document.write( "\n" ); document.write( "\"%288%2F3%29+x+-+y+=+26%2F3+\"\r
\n" ); document.write( "\n" ); document.write( "\"y=x\"...or \"x-y=0\"\r
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Solved by pluggable solver: Solve the System of Equations by Graphing

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\n" ); document.write( " Let's look at the first equation \"%288%2F3%29x-y=26%2F3\"
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\n" ); document.write( " \"3%28%288%2F3%29x-y%29=3%2826%2F3%29\" Multiply both sides of the first equation by the LCD 3
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\n" ); document.write( " \"8x-3y=26\" Distribute
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\n" ); document.write( " So our new system of equations is:
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\n" ); document.write( " \"8x-3y=26\"
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\n" ); document.write( " \"1x-y=0\"
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\n" ); document.write( " In order to graph these equations, we need to solve for y for each equation.
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\n" ); document.write( " So let's solve for y on the first equation
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\n" ); document.write( " \"8x-3y=26\" Start with the given equation
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\n" ); document.write( " \"-3y=26-8x\" Subtract \"8+x\" from both sides
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\n" ); document.write( " \"-3y=-8x%2B26\" Rearrange the equation
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\n" ); document.write( " \"y=%28-8x%2B26%29%2F%28-3%29\" Divide both sides by \"-3\"
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\n" ); document.write( " \"y=%28-8%2F-3%29x%2B%2826%29%2F%28-3%29\" Break up the fraction
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\n" ); document.write( " \"y=%288%2F3%29x-26%2F3\" Reduce
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\n" ); document.write( " Now lets graph \"y=%288%2F3%29x-26%2F3\" (note: if you need help with graphing, check out this solver)
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%288%2F3%29x-26%2F3%29+\" Graph of \"y=%288%2F3%29x-26%2F3\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"1x-y=0\" Start with the given equation
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\n" ); document.write( " \"-y=0-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"-y=-x%2B0\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B0%29%2F%28-1%29\" Divide both sides by \"-1\"
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\n" ); document.write( " \"y=%28-1%2F-1%29x%2B%280%29%2F%28-1%29\" Break up the fraction
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\n" ); document.write( " \"y=x%2B0\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=x%2B0\" to our first plot to get:
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%288%2F3%29x-26%2F3%2Cx%2B0%29+\" Graph of \"y=%288%2F3%29x-26%2F3\"(red) and \"y=x%2B0\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"26%2F5\",\"26%2F5\") (note: you might have to adjust the window to see the intersection)

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