Question 128727
x varies directly as the square of s and inversely as t. 
EQUATION:
x = k[s^2/t]
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how does x change when s is doubled? 
x = k[(2s)^2/t]
x = k[4s^2/t]
x = 4[k(s^2/t)]
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x gets multiplied by 4
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when both s and t are doubled?
x = k[(2s)^2/(2t)]
x = k[4s^2/2t]
x = k[2s^2/t]
x = 2[ks^2/t]
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x gets mltiplied by 2
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Cheers,
Stan H.