Find the area of the triangle determined by its 3 vertices \( P(0,-1,1) \) \( Q(1,-2,1) \), and \( R(1,0,1) \)

Si \( P=(1,1) \) y \( Q=(2,2) \), la magnitud \( (|\overrightarrow{P Q}|) \) y dirección \( (\theta) \) del vector \( \overrightarrow{P Q} \) son, respectivamente

Draw a graph of the line that contains the given point and has the given slope. \( (0,1) ; m=-3 \)

Draw a graph of the line that contains the given point and has the given slope. \( (-5,0) ; m=\frac{1}{5} \)

7. A village with an actual area of \( 1 \mathrm{~km}^{2} \) is represented by an area of \( 4 \mathrm{~cm}^{2} \) on a map. (a) Express the scale of this map in the form \( 1: n \), where \( n \) is an integer.

The midpoint between two points is \( \{1,5\rangle \). One of those points is \( \{8,3\rangle \), find the other.