#### Answer

a.)undefined
b.) 0
c.)$\frac{-5}{12}$
d.)$\frac{-4}{3}$

#### Work Step by Step

a.) (6,4) and (6,-3)
Slope formula m =$\frac{y2-y1}{x2-x1}$ = $\frac{-3-4}{6-6}$ = $\frac{-7}{0}$ = undefined
b.)(1,4)and (-5,4)
Slope formula m =$\frac{y2-y1}{x2-x1}$ = $\frac{4-4}{-5-1}$ = $\frac{0}{-6}$ = 0
c.)(-5,2) and (7,-3)
Slope formula m =$\frac{y2-y1}{x2-x1}$ = $\frac{-3-2}{7+5}$ = $\frac{-5}{12}$
d.)(x-3,y+2) and(x,y-2)
Slope formula m =$\frac{y2-y1}{x2-x1}$ = $\frac{y-2-y-2}{x-x+3}$ = $\frac{-4}{3}$