document.write( "Question 26595: The directions say to find the equation of the line passing through the given points, use function notation.\r
\n" ); document.write( "\n" ); document.write( "(8,-3), (4,-8)
\n" ); document.write( "i'm not sure what to do, please help, thanks \n" ); document.write( "
Algebra.Com's Answer #14471 by longjonsilver(2297)\"\" \"About 
You can put this solution on YOUR website!
the straight line will have the form y=mx+c or in function notation, f(x) = mx+c.\r
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\n" ); document.write( "\n" ); document.write( "We need the gradient, m first.\r
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\n" ); document.write( "\n" ); document.write( "m = (change in y)/(change in x)
\n" ); document.write( "m = (-8 - -3)/(4 - 8)
\n" ); document.write( "m = (-8 + 3)/(4 - 8)
\n" ); document.write( "m = (-5)/(-4)
\n" ); document.write( "m = 5/4\r
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\n" ); document.write( "\n" ); document.write( "so, f(x) = (5/4)x + c\r
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\n" ); document.write( "\n" ); document.write( "Now for c... we need to know x and y. We do...we have 2 versions to use --> the 2 sets of coordinates. Pick one pair...the easiest looking. Here, God knows, so just pick one. I pick (8,-3)\r
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\n" ); document.write( "\n" ); document.write( "-3 = (5/4)(8) + c
\n" ); document.write( "-3 = 5*2 + c
\n" ); document.write( "-3 = 10 + c
\n" ); document.write( "--> c = -13\r
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\n" ); document.write( "\n" ); document.write( "so, the function is f(x) = (5/4)x - 13\r
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\n" ); document.write( "\n" ); document.write( "jon.
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