On graph paper, plot $ΔABC$ if $A\left(-1,-1\right)$, $B\left(1,9\right)$, and $C\left(7,5\right)$.  

1. Find the midpoint of $\overline{AB}$ and label it $D$. Also find the midpoint of $\overline{BC}$ and label it $E$.

2. Find the length of the midsegment, $\overline{DE}$. Use it to predict the length of $\overline{AC}$.

3. Now find the length of $\overline{AC}$ and compare it to your prediction from (b).