Solve the equation LaTeX:  \displaystyle \log_{10}(x + 9986)-\log_{10}(x + 986)=1 .

Using the quotient property of logarithms gives LaTeX:  \displaystyle \log_{10}\frac{x + 9986}{x + 986} = 1 . Making both sides of the equation exponents on the base LaTeX:  \displaystyle 10 gives LaTeX:  \displaystyle \frac{x + 9986}{x + 986}=10 . Clearing the fractions by multiplying by the LCD gives LaTeX:  \displaystyle x + 9986=10 x + 9860 . Isolating LaTeX:  \displaystyle x gives LaTeX:  \displaystyle x = 14 .