35
Solve for $x$ :
\[
\log (x)+\log (x+2)=2
\]
\(\boxed{x = -1 + \sqrt{101}}\) is the only solution
Step 1 :\(\log (x(x+2))=2\)
Step 2 :\(\log (x^2+2x)=2\)
Step 3 :\(10^2 = x^2 + 2x\)
Step 4 :\(100 = x^2 + 2x\)
Step 5 :\(x^2 + 2x - 100 = 0\)
Step 6 :\(x = \frac{-2 \pm \sqrt{(2)^2 - 4(1)(-100)}}{2(1)}\)
Step 7 :\(x = \frac{-2 \pm \sqrt{4 + 400}}{2}\)
Step 8 :\(x = \frac{-2 \pm \sqrt{404}}{2}\)
Step 9 :\(x = -1 \pm \sqrt{101}\)
Step 10 :Check the solutions in the original equation
Step 11 :\(x = -1 + \sqrt{101}\) is a valid solution
Step 12 :\(x = -1 - \sqrt{101}\) is not a valid solution
Step 13 :\(\boxed{x = -1 + \sqrt{101}}\) is the only solution