Incorrect Answer For MiniQuestion?

For the mini question, shouldn't the answer be
$$r={\sqrt{(sa)(sb)(sc)}\over s} $$instead of
$$r={\sqrt{(sa)(sb)(sc)\over s}} $$The denominator shouldn't be inside the square root, right?

@aaronwang Thanks for asking! Actually, the area formula equals \( \sqrt{ s(sa)(sb)(sc)},\) which I can write like this: \(\sqrt{s}\sqrt{(sa)(sb)(sc)}.\) So since the area of the triangle is equal to \(rs,\) dividing this by \(s\) makes the \(\sqrt{s}\) cancel out but leaves a \(\sqrt{s}\) on the bottom.
$$\begin{aligned} r &= \frac{\textcolor{red}{\sqrt{s}} \sqrt{(sa)(sb)(sc)}}{\textcolor{red}{s}} \\\\ &= \frac{\textcolor{red}{\sqrt{s}} \sqrt{(sa)(sb)(sc)}}{\textcolor{red}{\sqrt{s}\sqrt{s}}} \\\\ &= \frac{\sqrt{(sa)(sb)(sc)} }{\sqrt{s}}\\ \end{aligned} $$ 
@debbie Ah, ok! So since the denominator is
$$\sqrt{s} $$it gets combined into that bigger square root.

This post is deleted! 
You got it!