document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1120615>Question 1120615</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A function f is given by f(4x-1) = 4x2+5.  Evaluate f(15).\r<BR>\n" );
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document.write( "Answer: f(15) = Answer<BR>\n" );
document.write( "905<BR>\n" );
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document.write( "905 would be the answer if the function were defined as f(x) = 4x^2+5:<br><BR>\n" );
document.write( "f(15) = 4(15^2)+5 = 4(225)+5 = 900+5 = 905<br><BR>\n" );
document.write( "But the function is defined as f(4x-1) = 4x^2+5.  To evaluate f(15), you need to determine the value of x that makes 4x-1 equal to 15.<br><BR>\n" );
document.write( "4x-1 = 15<BR>\n" );
document.write( "4x = 16<BR>\n" );
document.write( "x = 4<br><BR>\n" );
document.write( "THAT is the value you need to substitute into the expression 4x^2+5 to get the answer. </SPAN>\n" );
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