document.write( "Question 936106: If the line passing through the points
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Algebra.Com's Answer #569573 by MathLover1(20849)\"\" \"About 
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If the line passing through the points
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\n" ); document.write( "\n" ); document.write( " and parallel to the line passing through the points
\n" ); document.write( "(\"12\", \"5\") and (\"a+%2B+2\",\"+1\")\r
\n" ); document.write( "\n" ); document.write( "to find equations, start with slope-intercept form and find a slope and y-intercept:\r
\n" ); document.write( "\n" ); document.write( "\"y=mx%2Bb\" use point (\"1\", \"8\")\r
\n" ); document.write( "\n" ); document.write( "\"8=m%2A1%2Bb+\"\r
\n" ); document.write( "\n" ); document.write( "\"8=m%2Bb\"\r
\n" ); document.write( "\n" ); document.write( "\"m=8-b\"............eq.1\r
\n" ); document.write( "\n" ); document.write( "for parallel line:\r
\n" ); document.write( "\n" ); document.write( "\"y=mx%2Bb\" use point (\"12\", \"5\")\r
\n" ); document.write( "\n" ); document.write( "\"5=m%2A12%2Bb\" \r
\n" ); document.write( "\n" ); document.write( "\"5=12m%2Bb\"\r
\n" ); document.write( "\n" ); document.write( "\"12m=5-b\"\r
\n" ); document.write( "\n" ); document.write( "\"m=%285-b%29%2F12\"...........eq.2\r
\n" ); document.write( "\n" ); document.write( "the parallel line will have same slope: so, we have\r
\n" ); document.write( "\n" ); document.write( "\"8-b=%285-b%29%2F12\".....solve for \"b\"\r
\n" ); document.write( "\n" ); document.write( "\"96-12b=5-b\"\r
\n" ); document.write( "\n" ); document.write( "\"96-5=12b-b\"\r
\n" ); document.write( "\n" ); document.write( "\"91=11b\"\r
\n" ); document.write( "\n" ); document.write( "\"b=91%2F11\"\r
\n" ); document.write( "\n" ); document.write( "then slope of the first line is: \r
\n" ); document.write( "\n" ); document.write( "\"m=8-b\" => \"m=8-91%2F11=88%2F11-91%2F11=-3%2F11\"\r
\n" ); document.write( "\n" ); document.write( "and equation of first line is:
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\n" ); document.write( "\"y=-%283%2F11%29x%2B91%2F11\" use point (\"a\", \"1\") to find \"a\"\r
\n" ); document.write( "\n" ); document.write( "\"1=-%283%2F11%29a%2B91%2F11\" ..........solve for \"a\"\r
\n" ); document.write( "\n" ); document.write( "\"%283%2F11%29a=91%2F11-1\"\r
\n" ); document.write( "\n" ); document.write( "\"3a%2F11=91%2F11-11%2F11\"\r
\n" ); document.write( "\n" ); document.write( "\"3a%2F11=80%2F11\" ...if denominators same then\r
\n" ); document.write( "\n" ); document.write( "\"3a=80\"\r
\n" ); document.write( "\n" ); document.write( "\"a=80%2F3\"
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\n" ); document.write( "\"a=26.66666666666667\"\r
\n" ); document.write( "\n" ); document.write( "\"a=26.7\"=> the point is (\"a\", \"1\")=(\"26.7\", \"1\")\r
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\n" ); document.write( "\n" ); document.write( "find second equation:\r
\n" ); document.write( "\n" ); document.write( "slope is same \"m+=-3%2F11\" find \"b\"
\n" ); document.write( "\"-3%2F11+=%285-b%29%2F12\"
\n" ); document.write( "\"-%283%2F11%2912=5-b\"
\n" ); document.write( "\"b=36%2F11\"\r
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\n" ); document.write( "\n" ); document.write( "so, second equation is:\r
\n" ); document.write( "\n" ); document.write( "\"y=-%283%2F11%29x%2B3.27\" use point (\"a+%2B+2\", \"1\")\r
\n" ); document.write( "\n" ); document.write( "\"1=-%283%2F11%29%28a+%2B+2%29%2B3.27\"
\n" ); document.write( "\"1-3.27=%28-3%2F11%29%28a+%2B+2%29\"
\n" ); document.write( "\"-2.27%2F%28-3%2F11%29=a+%2B+2\"
\n" ); document.write( "\"2.27%2F0.27=a+%2B+2\"\r
\n" ); document.write( "\n" ); document.write( "\"8.4=a%2B2\"
\n" ); document.write( "\"a=8.4-2\"
\n" ); document.write( "\"a=6.4\" => the point is (\"a+%2B+2\",\"+1\")=(\"6.4+%2B+2\", \"1\")=(\"8.4\", \"1\")\r
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