document.write( "Question 635628: consider a linear function y=a+bx if f(2)=-5 f(7)=10 what is f(-4)? \n" ); document.write( "

Algebra.Com's Answer #400432 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "What you ask cannot be done. You defined the function

and then gave data about the function

evaluated at a couple of points. What would you say if I took you to a concert where two new bands were playing, but I only let you listen to the first one but asked your opinion on the second one?\r
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\n" ); document.write( "\n" ); document.write( "Be that as it may, I suspect you meant to say \"consider a linear function

. If

, and ...\"\r
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\n" ); document.write( "\n" ); document.write( "In that case, by substitution:\r
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\n" ); document.write( "\n" ); document.write( "and\r
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\n" ); document.write( "\n" ); document.write( "Giving you the following 2X2 linear system:\r
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\n" ); document.write( "\n" ); document.write( "Solve the system by any convenient means (it lends itself nicely to the elimination method), and once you have the values of

and

your function is fully defined. After that, evaluating

is trivial.\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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