Respuesta :

We have this equation:

[tex]\log(x) + \log(x + 99) = 2[/tex]

First, combine both logarithms using the multiplication property and simplify the expression.

[tex]\log[x(x + 99)] = 2[/tex]

[tex]\log[ {x}^{2} + 99x ] = 2[/tex]

Now, use the definition of logarithm to transform the equation.

[tex] {10}^{2} = {x}^{2} + 99x[/tex]

[tex] {x}^{2} + 99x - 100 = 0[/tex]

Finally, use the quadratic formula to solve the equation.

[tex]x = \frac{ -99 ± \sqrt{ {99}^{2} - 4 \times 1 \times ( - 100)} }{2 \times 1} [/tex]

With this, we can say that the solution set is:

  • x = 1
  • x = -100

We cannot choose x = -100 as a solution because we cannot have a negative logarithm. The only solution is x = 1.

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