Question 755407
suppose z varies directly as x and inversly as the square of y. 
z = k*x/y^2
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Solve for "k" using "If x=5 and y=2, then z=40". 
40 = k*5/(2^2)
160 = 5k
k = 160/5
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Equation:
z = (160/5)x/y^2
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find z when x=6 and y=4
z = (160/5)*6/16
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z = 10*6/5
z = 12
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Cheers,
Stan H.
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