SOLUTION: If z is jointly proportional to x and y, and z =18 when x =0.4 and y =3 find z when x= 0.6 and y= 4

Algebra ->  Radicals -> SOLUTION: If z is jointly proportional to x and y, and z =18 when x =0.4 and y =3 find z when x= 0.6 and y= 4      Log On


   

Question 1134152: If z is jointly proportional to x and y, and z =18 when x =0.4 and y =3 find z when x= 0.6 and y= 4
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The language used tells you everything to arrange the starting equations and find proportionality or variation constant.

z=kxy
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k=z%2F%28xy%29
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k=18%2F%280.4%2A3%29
k=15
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highlight%28z=15%2Axy%29

Find z when x=0.6 and y=4;
substitute for those and evaluate!