document.write( "Question 1204752: If 6^(2x+1) = k, then 6^(4x+3) equals\r
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Algebra.Com's Answer #841217 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Here's what to do in an EMERGENCY, but only in an EMERGENCY,\r\n" );
document.write( "and only on a multiple-choice test where you don't have to\r\n" );
document.write( "show your work.\r\n" );
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document.write( "If you run into a problem like this on a multiple-choice \r\n" );
document.write( "test and don't know what to do, and are completely stuck, \r\n" );
document.write( "then here is a trick that works a lot of the time. Some other\r\n" );
document.write( "tutors here will frown on me for telling you this, but it \r\n" );
document.write( "works sometimes on certain problems. \r\n" );
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document.write( "Substitute x=0.\r\n" );
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document.write( "Then 6^(2*0+1) = 6 = k, then 6^(4*0+3) = 6^3 = 216 \r\n" );
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document.write( "Then substitute 6 for k in every one of the choices:\r\n" );
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document.write( "A) 12k = 12(6) = 72\r\n" );
document.write( "That's not 216, so that eliminates A\r\n" );
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document.write( "B) k^2 + 6 = (6)^2 + 6 = 42\r\n" );
document.write( "That's not 216, so that eliminates B \r\n" );
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document.write( "C) 6k^2 = 6(6)^2 = 6(36) = 216  \r\n" );
document.write( "That IS 216, but that only means it's POSSIBLY the right choice.\r\n" );
document.write( "For it happens sometimes that one of the others will also be 216.\r\n" );
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document.write( "D) 2k + 6 = 2(6) + 6 = 18.\r\n" );
document.write( "That's not 216, so that eliminates D\r\n" );
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document.write( "E) 36k^2 = 36(6)^2 = 1296\r\n" );
document.write( "That's not 216, so that eliminates E\r\n" );
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document.write( "So we know the correct choice is C.\r\n" );
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document.write( "If another one of them had also come out 216, then\r\n" );
document.write( "you could do it again by substituting x=1 or x=-1. \r\n" );
document.write( "But if you're short on time, you still have a better \r\n" );
document.write( "chance of guessing correctly.\r\n" );
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document.write( "Also sometimes, on some problems, substituting 0 in what's\r\n" );
document.write( "given and then in all the choices is the easiest method!\r\n" );
document.write( "Sometimes you can do it in your head! I have actually used \r\n" );
document.write( "it myself to save time even though I knew how to get the \r\n" );
document.write( "solution the regular way! \r\n" );
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document.write( "As I mentioned above, sometimes substituting 1 or -1 is \r\n" );
document.write( "better than 0.  Sometimes substituting 0 causes a denominator \r\n" );
document.write( "to be 0. Other times other numbers work better. So you can\r\n" );
document.write( "improvise on this method.  But I'd better warn you, you'd\r\n" );
document.write( "better not rely on this method!  It won't save you if you\r\n" );
document.write( "don't understand the material! \r\n" );
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document.write( "Edwin
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