document.write( "Question 135303: Solve the system of equations: 9^(3x-y)=(1/81)^-1 and
\n" ); document.write( " (sqrt5^(2x-y))=1 \n" ); document.write( "
Algebra.Com's Answer #99180 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Solve the system of equations:
\n" ); document.write( ":
\n" ); document.write( "9^(3x-y)=(1/81)^-1
\n" ); document.write( "and
\n" ); document.write( "(sqrt5^(2x-y))=1
\n" ); document.write( ":
\n" ); document.write( "On the 1st equation, ^-1 is the reciprocal so we have:
\n" ); document.write( " 9^(3x-y)= 81
\n" ); document.write( ":
\n" ); document.write( "On the 2nd equation we can get rid of the radical by squaring both sides
\n" ); document.write( "5^(2x-y)) = 1
\n" ); document.write( ":
\n" ); document.write( "so we have:
\n" ); document.write( "\"9%5E%283x-y%29+=+81\"
\n" ); document.write( "and
\n" ); document.write( "\"5%5E%282x-y%29+=+1\"
\n" ); document.write( ":
\n" ); document.write( "In the 1st equation we ask, \"What exponent of 9 = 81\" Obviously its 9^2 = 81
\n" ); document.write( "Therefore:
\n" ); document.write( "3x - y = 2
\n" ); document.write( ":
\n" ); document.write( "On the second equation, What exponent of 5 = 1. We know that an exponent of 0 makes any number = 1
\n" ); document.write( " 5^0 = 1; Therefore 2x - y = 0
\n" ); document.write( ":
\n" ); document.write( "Solve these two equation using elimination
\n" ); document.write( "3x - y = 2
\n" ); document.write( "2x - y = 0
\n" ); document.write( "-----------Subtracting eliminates y
\n" ); document.write( "x = 2
\n" ); document.write( ":
\n" ); document.write( "3(2) - y = 2
\n" ); document.write( "-y = 2 - 6
\n" ); document.write( "-y = -4
\n" ); document.write( "y = 4
\n" ); document.write( ":
\n" ); document.write( "You can check this using these values in the original equation
\n" ); document.write( " \n" ); document.write( "
\n" );