Chapter 1 - Tools of Geometry - 1-8 Perimeter, Circumference, and Area - Practice and Problem-Solving Exercises - Page 67: 65

a) 5.8 b) (-1.5,5.5)

a) Use the distance formula: $d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$ $d=\sqrt{(-3-0)^2+(8-3)^2}$ $d=\sqrt{(-3)^2+(5)^2}$ $d=\sqrt{9+25}$ $d=\sqrt{34}$ $d=5.8$ b) Use the midpoint formula: $M_x=\frac{x_1+x_2}{2}=\frac{0+(-3)}{2}=\frac{-3}{2}=-1.5$ $M_y=\frac{y_1+y_2}{2}=\frac{3+8}{2}=\frac{11}{2}=5.5$