document.write( "Question 948988: Graph each line
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\n" ); document.write( "\n" ); document.write( "Graph each line
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Algebra.Com's Answer #579279 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
1.
\n" ); document.write( "given: graph a line that has
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Solved by pluggable solver: FIND a line by slope and one point

\n" ); document.write( " What we know about the line whose equation we are trying to find out:
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  • it goes through point (3, 5)

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  • it has a slope of -1

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\n" ); document.write( " First, let's draw a diagram of the coordinate system with point (3, 5) plotted with a little blue dot:
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\n" ); document.write( " Write this down: the formula for the equation, given point \"x%5B1%5D%2C+y%5B1%5D\" and intercept a, is
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\n" ); document.write( " \"y=ax+%2B+%28y%5B1%5D-a%2Ax%5B1%5D%29\" (see a paragraph below explaining why this formula is correct)
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\n" ); document.write( " Given that a=-1, and \"system%28+x%5B1%5D+=+3%2C+y%5B1%5D+=+5+%29+\", we have the equation of the line:
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\n" ); document.write( " \"y=-1%2Ax+%2B+8\"
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\n" ); document.write( " Explanation: Why did we use formula \"y=ax+%2B+%28y%5B1%5D+-+a%2Ax%5B1%5D%29\" ? Explanation goes here. We are trying to find equation y=ax+b. The value of slope (a) is already given to us. We need to find b. If a point (\"x%5B1%5D\", \"y%5B1%5D\") lies on the line, it means that it satisfies the equation of the line. So, our equation holds for (\"x%5B1%5D\", \"y%5B1%5D\"): \"y%5B1%5D+=+a%2Ax%5B1%5D%2Bb\" Here, we know a, \"x%5B1%5D\", and \"y%5B1%5D\", and do not know b. It is easy to find out: \"b=y%5B1%5D-a%2Ax%5B1%5D\". So, then, the equation of the line is: \"+y=ax%2B%28y%5B1%5D-a%2Ax%5B1%5D%29+\".
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\n" ); document.write( " Here's the graph:
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\n" ); document.write( "\n" ); document.write( "Graph each line that has \"no\" slope, through (\"2\",\"-1\")\r
\n" ); document.write( "\n" ); document.write( "vertical lines have \"NO\" \"SLOPE\", it is parallel to y-axis passing through \"x=2\"\r
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