document.write( "Question 795285: there are 2 problems i dont know how to do can u pls help
\n" ); document.write( "1st problem : y varies directly as x and inversely as the square of z. y=30 when x=40 and z=2. find y when x=80 and z=4\r
\n" ); document.write( "\n" ); document.write( "2nd problem: if y varies as x and y=7 when x=6 find y when x=18
\n" ); document.write( " \n" ); document.write( "
Algebra.Com's Answer #480866 by Cromlix(4381)\"\" \"About 
You can put this solution on YOUR website!
1st problem : y varies directly as x and inversely as the square of z. y=30 when x=40 and z=2. find y when x=80 and z=4.
\n" ); document.write( "y = kx/z^2
\n" ); document.write( "To find k the constant of variation,insert values given.
\n" ); document.write( "y = kx/z^2
\n" ); document.write( "30 = k*40/2^2
\n" ); document.write( "30 = k40/4
\n" ); document.write( "30 = k10
\n" ); document.write( "k = 30/10
\n" ); document.write( "k = 3.
\n" ); document.write( "Your formula:-
\n" ); document.write( "y = 3x/z^2
\n" ); document.write( ".....
\n" ); document.write( "y = 3*80/16
\n" ); document.write( "y = 240/16
\n" ); document.write( "y = 15
\n" ); document.write( "......................
\n" ); document.write( "2nd problem: if y varies as x and y=7 when x=6 find y when x=18
\n" ); document.write( "y = kx
\n" ); document.write( "To find k insert values:
\n" ); document.write( "7 = k6
\n" ); document.write( "k = 7/6
\n" ); document.write( ".......
\n" ); document.write( "Your formula:
\n" ); document.write( "y = 7/6 x\r
\n" ); document.write( "\n" ); document.write( "y = 7/6 * 18
\n" ); document.write( "y = 21
\n" ); document.write( "..............
\n" ); document.write( "Hope this helps.
\n" ); document.write( ":-)
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