Problems 1a - 1c: Find the slope of the straight line that passes through the given points or state that the slope is undefined.

Help!?

1. (7, 4) and (1, 1)



2. (-3, 4) and (2, -1)


3. (-5, 3) and (-5, 2)

recall that slope = ∆y/∆x

so, if ∆x is 0, the slope is undefined

#1: ∆y/∆x = (1-4)/(1-7) = 3/6 = 1/2
#2: ∆y/∆x = (-1-4)/(2+3) = -5/5 = -1
#3: ∆y/∆x = -1/0 is undefined