Respuesta :

Given:

[tex]\ln x+\ln (x+14)=3[/tex]

Use the formula:

[tex]\ln ab=\ln a+\ln b[/tex][tex]\begin{gathered} \ln x+\ln (x+14)=3 \\ \ln x(x+14)=3 \\ x(x+14)=e^3 \\ x^2+14x=20.085 \end{gathered}[/tex]

solve the equation :

[tex]\begin{gathered} x^2+14x=20.085 \\ x^2+14x-20.085=0 \\ x=\frac{-14\pm\sqrt[]{14^2-4(1)(-20.085)}}{2} \\ x=\frac{-14\pm\sqrt[]{276.34}}{2} \\ x=\frac{-14\pm16.623}{2} \\ x=-7\pm8.312 \\ x=-7+8.312;x=-7-8.312 \\ x=1.312;x=-15.312 \end{gathered}[/tex]