We have:
* y = 3, Horizontal straight lines have zero slope, since the "rise" is zero.
Answer: 0
* 9x - 3y = 18, We rearrange to the slope form equation, which is: y = mx + b, so:
[tex]\begin{gathered} 9x-3y-9x=18-9x \\ -3y=18-9x \\ \frac{-3y}{-3}=\frac{18}{-3}-\frac{9x}{-3} \\ y=3x+6 \end{gathered}[/tex]
So the slope is 3.
Answer: 3
* (5,7) and (5, -8) the slope is given by the formula:
[tex]m=\frac{y2-y1}{x2-x1}=\frac{-8-7}{5-5}=\frac{-15}{0}[/tex]
So, the "run" is zero, and division by zero is not allowed.
Answer: undefined
* (-4, -1) and (-1, -7)
[tex]m=\frac{-7-(-1)}{-1-(-4)}=\frac{-7+1}{-1+4}=-\frac{6}{3}=-2[/tex]
Answer: - 2
