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Question Number 177361 by jlewis last updated on 04/Oct/22

4(16^((x+4))  × 5.2^(2x) =13

$$\mathrm{4}\left(\mathrm{16}^{\left({x}+\mathrm{4}\right)} \:×\:\mathrm{5}.\mathrm{2}^{\mathrm{2}{x}} =\mathrm{13}\right. \\ $$

Answered by a.lgnaoui last updated on 04/Oct/22

 2^2 (2^4 )^((x+4)) ×5.2^(2x) =13   5(2^(4x+18)  ×2^(2x) )=13   (2^(6x+18) )=((13)/5)      (6x+18)ln2=ln13−ln5   6x=((ln13−ln5)/(ln2))−18     x=((ln13−ln5−18.ln2)/(6.ln2))   ;(ln13=2,5649    ln5=1,6094    ln2=0,6931  )  x=((2,5649−1,6094−12,4758)/(4,1586))  x=−2,77

$$\:\mathrm{2}^{\mathrm{2}} \left(\mathrm{2}^{\mathrm{4}} \right)^{\left({x}+\mathrm{4}\right)} ×\mathrm{5}.\mathrm{2}^{\mathrm{2}{x}} =\mathrm{13} \\ $$$$\:\mathrm{5}\left(\mathrm{2}^{\mathrm{4}{x}+\mathrm{18}} \:×\mathrm{2}^{\mathrm{2}{x}} \right)=\mathrm{13} \\ $$$$\:\left(\mathrm{2}^{\mathrm{6}{x}+\mathrm{18}} \right)=\frac{\mathrm{13}}{\mathrm{5}}\:\:\: \\ $$$$\:\left(\mathrm{6}{x}+\mathrm{18}\right)\mathrm{ln2}=\mathrm{ln13}−\mathrm{ln5} \\ $$$$\:\mathrm{6}{x}=\frac{\mathrm{ln13}−\mathrm{ln5}}{\mathrm{ln2}}−\mathrm{18} \\ $$$$\:\:\:{x}=\frac{\mathrm{ln13}−\mathrm{ln5}−\mathrm{18}.\mathrm{ln2}}{\mathrm{6}.\mathrm{ln2}}\:\:\:;\left(\mathrm{ln13}=\mathrm{2},\mathrm{5649}\:\:\:\:\mathrm{ln5}=\mathrm{1},\mathrm{6094}\:\:\:\:\mathrm{ln2}=\mathrm{0},\mathrm{6931}\:\:\right) \\ $$$${x}=\frac{\mathrm{2},\mathrm{5649}−\mathrm{1},\mathrm{6094}−\mathrm{12},\mathrm{4758}}{\mathrm{4},\mathrm{1586}} \\ $$$${x}=−\mathrm{2},\mathrm{77} \\ $$

Commented by a.lgnaoui last updated on 04/Oct/22

excuse moi je ferai le necessaire pour   minimiser le zoom sinon  je prendrai l image d′ecran)  thank you.

$${excuse}\:{moi}\:{je}\:{ferai}\:{le}\:{necessaire}\:{pour}\: \\ $$$${minimiser}\:{le}\:{zoom}\:{sinon} \\ $$$$\left.{je}\:{prendrai}\:{l}\:{image}\:{d}'{ecran}\right) \\ $$$${thank}\:{you}. \\ $$

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