Question 174494
A(-1,0), B(3,3), C(6,-1), D(2,-4). 
slopes:
AB=(3-0)/(3+1)=3/4
DC=(-4+1)/(2-6)=3/4 THUS THESE 2 LINES ARE PARALLEL.
slopes:
BC=(-1-3)/6-3)=-4/3=-4/3
AD=(-4-0)/(2+1)=-4/3 THESE 2 LINES ARE PARALLEL & PERPENDICULAR TO THE AB & DC LINES.
THUS THIS IS A SQUARE FIGURE.