Question 1140534
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4*(5x+2) = 3x^2 + 1


3x^2 - 20x - 7 = 0


{{{x[1,2]}}} = {{{(20 +- sqrt(20^2 + 4*3*7))/(2*3)}}} = {{{(20 +- sqrt(484))/6}}} = {{{(20 +- 22)/6}}}.


Only positive root makes sense  x = {{{(20 + 22)/6}}} = {{{42/6}}} = 7.


<U>ANSWER</U>.  The base is 7.
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