22. the coordinates are:
[tex]Q(-8,7),R(-7,2),S(-8,13),t(-11,-2)[/tex]So to know if the are parallel or perpendicular we have to calculate the slopes so:
For QR
[tex]m=\frac{2-7}{-7-(-8)}=-\frac{5}{1}=-5[/tex]For ST
[tex]m=\frac{-2-13}{-11-(-8)}=-\frac{15}{3}[/tex]So they are not parallel or perpendicular.
23. the coordinates are:
[tex]Q(-1,4),R(-1,-9),S(11,-2),T(11,6)[/tex]Now the slopes are
For QR
[tex]m=\frac{-9-4}{-1-(-1)}[/tex]This is undefine so is a vertival line
for ST:
[tex]m=\frac{8-(-2)}{11-11}[/tex]Is undefine so is also a vertical line, this means that they are parallel