document.write( "Question 478211: Find an equation of the line that contains the given of points (23,27)(5,9) \n" ); document.write( "
Algebra.Com's Answer #327654 by Alan3354(69443)\"\" \"About 
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Find an equation of the line that contains the given of points (23,27)(5,9)
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\n" ); document.write( "Determinants is the best way.
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\n" ); document.write( "|+x +y +1|
\n" ); document.write( "|23 27 +1| = 0
\n" ); document.write( "|+5 +9 +1|
\n" ); document.write( "The +'s are for alignment
\n" ); document.write( "------
\n" ); document.write( "x*(27-9) - y*(23-5) + 23*9-5*27 = 0
\n" ); document.write( "18x - 18y = -72
\n" ); document.write( "x - y = -4
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\n" ); document.write( "If you're not familiar with determinants:
\n" ); document.write( "Find the slope, m = diffy/diffx
\n" ); document.write( "(23, 27)
\n" ); document.write( "( 5, 9)
\n" ); document.write( "--------- Subtract
\n" ); document.write( "18, 18
\n" ); document.write( "m = 18/18 = 1
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\n" ); document.write( "Use y = mx + b and either point to find b, the y-intercept
\n" ); document.write( "9 = 1*5 + b
\n" ); document.write( "b = 4
\n" ); document.write( "------
\n" ); document.write( "--> y = x + 4
\n" ); document.write( "Same equation, different form\r
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