Graph and find the slope for x equals 3?

Answer 1

The graph of x = 3 will be a straight vertical (up and down) line at 3 on the x-axis.

To find the slope you can do the "Rise over Run" method.
Alternatively, you can use the formula y2 - y1/x2 - x1

For this method, we need to find two points on the line. Since this is a vertical line at 3 on the x-axis, the x value for both points will be 3 and we can pick any two values for y.

So for example, (3,0) and (3,1) are both valid points on this line. Likewise, (3,999) and (3,454) are also valid points.

So, lets use (3,0) and (3,1)
y2 = 1
y1 = 0
x2 = 3
x1 = 3

so 1 - 0/0 - 0 = 1/0

Since we can not divide by zero, the slope of the line is "undefined".
If this method confuses you, you can work it out the "Rise over Run" way.
Since the vertical line is not "running" anywhere, we can say that the Run for this line is zero and anything divided by zero is "undefined".