You can use the formulas:
Area = [tex] \frac{base*altitude}{2} [/tex]
AB = [tex] \sqrt{ ( x_{B}- x_{A} )^{2} + ( y_{B}- y_{A} )^{2} } [/tex]
P(-2, 1), Q(6, 1), R(4, -3), S(4, 1)
Base = PQ = [tex] \sqrt{ 8^{2} + 0^{2} } =8[/tex]
Altitude = SR = [tex] \sqrt{ (0^{2} + (4^{2} } =4[/tex]
Area = [tex] \frac{8*4}{2} =16[/tex]
The right answer is : B. 16
