Question 1074366
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x*(x+4) = 160,

x^2 + 4x - 160 = 0,

x = {{{-4 +- sqrt(16 + 4*160))/2}}} = {{{(-4 +- sqrt(656))/2}}}.


The only meaningful positive root is {{{(sqrt(656) - 4)/2}}} = 10.806 (approximately).
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