document.write( "Question 81965: Hi. Desperately need help with these. I think I got the answer to one, but am totally stuck on the other. Here they are:\r
\n" ); document.write( "\n" ); document.write( "Solve 4^x+2 = 9^x-1\r
\n" ); document.write( "\n" ); document.write( "Solve 7^x+2 = 10^x-3 (I got 3+2log7 ((over)) 1-log7) Is that right?\r
\n" ); document.write( "\n" ); document.write( "Please help!! Thanks so much! \n" ); document.write( "
Algebra.Com's Answer #58793 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Solve 4^x+2 = 9^x-1
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\n" ); document.write( "Assume you mean:
\n" ); document.write( "\"4%5E%28%28x%2B2%29%29+=++9%5E%28%28x-1%29%29\"
\n" ); document.write( ":
\n" ); document.write( "Write the log equiv of exponents:
\n" ); document.write( "(x+2)*log(4) = (x-1)* log(9)
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\n" ); document.write( "Find the log of 4 and 9
\n" ); document.write( ".602(x+2) = .954(x-1)
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\n" ); document.write( "Multiply what's inside the brackets and solve for x:
\n" ); document.write( ".602x + 1.204 = .954x - .954
\n" ); document.write( ":
\n" ); document.write( "1.204 + .954 = .954x - .602x
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\n" ); document.write( "2.158 = .352x
\n" ); document.write( ":
\n" ); document.write( "x = 2.158/.352
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\n" ); document.write( "x = 6.13
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\n" ); document.write( "Check solution on a calc:
\n" ); document.write( "4^8.13 = 78478
\n" ); document.write( "and
\n" ); document.write( "9^5.13 = 78571, not exact because of rounding off
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\n" ); document.write( "Solve 7^x+2 = 10^x-3
\n" ); document.write( ":
\n" ); document.write( "Do this one exactly the same way:
\n" ); document.write( "\"7%5E%28%28x%2B2%29%29+=+10%5E%28%28x-3%29%29\"
\n" ); document.write( ":
\n" ); document.write( ".845(x+2) = 1(x-3); log of 10 is 1
\n" ); document.write( ":
\n" ); document.write( ".845x + 1.69 = x - 3
\n" ); document.write( ":
\n" ); document.write( "1.69 + 3 = x - .845x
\n" ); document.write( ":
\n" ); document.write( "4.69 = .155x
\n" ); document.write( ":
\n" ); document.write( "x = 4.69/.155
\n" ); document.write( ":
\n" ); document.write( "x = 30.258
\n" ); document.write( ":
\n" ); document.write( "Check solution on a calc
\n" ); document.write( "7^32.258 = 1.82(10^27)
\n" ); document.write( "10^27.258 = 1.81(10^27) \n" ); document.write( "
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