Answer:
A) The line goes up when moving right to left
False. The slope being zero means there is no change in elevation or height. The line is completely flat and horizontal. Recall that slope = rise/run. If the slope is 0, then the rise must be 0.
B) The line goes down when moving right to left.
False. The same reasoning as choice A
C) The line is horizontal
True. Any line with a slope of zero is going to be horizontal. For instance, the equation y = 0x+5 is the horizontal line through 5 on the y axis.
D) The line is vertical
False. This contradicts choice C above. Vertical lines have undefined slopes which aren't numbers due to the fact we cannot divide by zero.
E) The run is zero
False. The run can be any number but zero. For example, slope = 0 = 0/1 or 0 = 0/5. Dividing zero over any nonzero number leads to 0.
F) The rise is zero
True. As mentioned before in previous answer choices (see choice A in particular).
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In summary, there are only two true statements and they are choice C and choice F. The other statements are false.
Explanation: