You are told that the y is proportional to x^2 and that when y=75, x=5. Find a formula for x in terms of y.
If we know that y is proportional to x2 then we using the given values we can write 75= 52 --> 75=25, however this is obviously not true but all that remains is to multiply the 52 by 3 which gives us 75=3(52) --> 75=75
JP
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