document.write( "Question 1157199: Hi, I needed to figure out the answer to one of my math problems, which was \"to write a linear function f with the values f(−2)=3 and f(5)=7\". Can you please help me figure out the answer to my problem? \n" ); document.write( "

Algebra.Com's Answer #780028 by math_helper(2461) $\"\"$ $\"About$

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document.write( "Ok, linear means  f(x) = kx + c   where k and c are constants.  Notice how x is raised only to the first power, that's what makes it linear.\r
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document.write( "f(-2) = 3 tells us   k(-2) + c = 3
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document.write( "f(5) = 7  tells us   k(5) + c = 7
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document.write( "  Subtract the bottom equation from the top, -7k = -4  --> k=4/7
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document.write( "  Plug in k=4/7 into one of the equations and solve for c:
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document.write( "      -2(4/7) + c = 3
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document.write( "        -8/7 + c = 3
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document.write( "          c = 3 + 8/7 = 21/7 + 8/7 = 29/7\r
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