Question 180350
x varies directly as the square of s and inversely as t.
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x = k[s^2/t]
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How does x change when s is doubled? 
Change from s to 2s to get:

x = k[(2s)^2/t] = k[4s^2/t] = 4[k[s^2/t]]
From this you can see that the value of x is multiplied by 4.
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When both s and t are doubled?)))
Change s to 2s and change t to 2t to get:

x = k[(2s)^2/(2t)] = k[4s^2/2t] = k[2s^2/t] = 2[k[s^2/t]]
From this you can see that the value of x is multiplied by 2.

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Cheers,
Stan H.
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