document.write( "Question 1006309: If f(x) is a linear function, what is the value of n?
\n" ); document.write( "I made a little chart of how the question looks:\r
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\n" ); document.write( "-1 -10 \r
\n" ); document.write( "\n" ); document.write( "n 20\r
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Algebra.Com's Answer #622467 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Step 1) Find the slope of the line through the two points (-4,-25) and (-1,-10)\r
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\n" ); document.write( "\n" ); document.write( "First point (first row of table):
\n" ); document.write( "(x1,y1) = (-4,-25)\r
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\n" ); document.write( "\n" ); document.write( "Second point (second row of table):
\n" ); document.write( "(x1,y1) = (-1,-10)\r
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\n" ); document.write( "\n" ); document.write( "Slope formula
\n" ); document.write( "m = (y2 - y1)/(x2 - x1)
\n" ); document.write( "m = (-10 - (-25))/(-1 - (-4))
\n" ); document.write( "m = (-10 + 25)/(-1 + 4)
\n" ); document.write( "m = (15)/(3)
\n" ); document.write( "m = 5\r
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\n" ); document.write( "\n" ); document.write( "The slope is m = 5\r
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\n" ); document.write( "\n" ); document.write( "Step 2) use y = mx+b, the slope found in step 1, and one of the points to find the value of b\r
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\n" ); document.write( "\n" ); document.write( "m = 5
\n" ); document.write( "x = -4
\n" ); document.write( "y = -25\r
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\n" ); document.write( "\n" ); document.write( "The x,y pair is found from the first row\r
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\n" ); document.write( "\n" ); document.write( "y = mx+b
\n" ); document.write( "y = 5x+b ... replace m with 5
\n" ); document.write( "y = 5(-4)+b ... replace x with -4
\n" ); document.write( "-25 = 5(-4)+b ... replace y with -25; solve for b
\n" ); document.write( "-25 = -20+b
\n" ); document.write( "-25 = b-20
\n" ); document.write( "-25+20 = b-20+20
\n" ); document.write( "-5 = b
\n" ); document.write( "b = -5\r
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\n" ); document.write( "\n" ); document.write( "The y intercept is b = -5\r
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\n" ); document.write( "\n" ); document.write( "Step 3) Form the equation/function\r
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\n" ); document.write( "\n" ); document.write( "We found that the slope is m = 5 and the y intercept is b = -5\r
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\n" ); document.write( "\n" ); document.write( "So y = mx+b turns into y = 5x - 5\r
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\n" ); document.write( "\n" ); document.write( "Now replace y with f(x) to get f(x) = 5x - 5\r
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\n" ); document.write( "\n" ); document.write( "Step 4) Use f(x) = 20 to find the value of x\r
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\n" ); document.write( "\n" ); document.write( "f(x) = 5x - 5
\n" ); document.write( "20 = 5x - 5 ... replace f(x) with 20; solve for x
\n" ); document.write( "20+5 = 5x - 5+5
\n" ); document.write( "25 = 5x
\n" ); document.write( "5x = 25
\n" ); document.write( "5x/5 = 25/5
\n" ); document.write( "x = 5\r
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\n" ); document.write( "\n" ); document.write( "The input x value of x = 5 produces the output f(x) value of 20\r
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\n" ); document.write( "\n" ); document.write( "So n = 5\r
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\n" ); document.write( "\n" ); document.write( "Final Answer: n = 5
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