document.write( "Question 163972: Hello I need to solve this and I havent done math for 5 years.could you please help me\r
\n" ); document.write( "\n" ); document.write( "what is the equation of th eline that contains the points with ( x, y ) coordinates ( -3, 7 ) and (5,-1)
\n" ); document.write( "thanks\r
\n" ); document.write( "\n" ); document.write( "tha answer is y= -x + 4 can you explain why>? \n" ); document.write( "
Algebra.Com's Answer #120810 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
If you are given two points, you can determine the slope from:
\n" ); document.write( "m = (y2-y1)/(x2-x1)
\n" ); document.write( "Our two points:( -3, 7 ) and (5,-1)
\n" ); document.write( "substituting it in, we get:
\n" ); document.write( "m = (-1-7)/(5-(-3))
\n" ); document.write( "m = (-8)/(5+3)
\n" ); document.write( "m = (-8)/(8)
\n" ); document.write( "m = -1
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\n" ); document.write( "Now that we know the slope (-1), we can use one of the two given points (say we use ( -3, 7 )) and plug it into the \"point-slope\" form of a line:
\n" ); document.write( " y – y1 = m(x – x1)
\n" ); document.write( " y – 7 = -1(x – (-3))
\n" ); document.write( " y – 7 = -1(x + 3)
\n" ); document.write( " y – 7 = -x - 3
\n" ); document.write( " y = -x + 4 (this is our equation of the line)\r
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