1) If $log_{5}(x^{2}+x)$ $-log_{5}(x+1)$ $=2$, then the value of $x$ is : A) 25 B) 10 C) 32 D) 5 Answer: Option AExplanation:$log_{5}(x^{2}+x)$ $-log_{5}(x+1)$ $=2$ $\Rightarrow log_{5}\left(\frac{x^{2}+x}{x+1}\right)$ $=2$ $\Rightarrow log_{5}\left[\frac{x(x+1)}{x+1}\right]$ $=2$ $\Rightarrow log_{5}x$ $=2$ $\Rightarrow x=5^{2}$ = 25.
