Answer:
see explanation
Explanation:
In relation to slopes of lines
• A horizontal line has a slope of zero
• A vertical line has an undefined slope
• A line sloping upwards from left to right has a positive slope
• A line sloping downwards from left to right has a negative slope
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Line 1
is a horizontal line and has a slope of zero
Line 2
slopes upwards from left to right and has a positive slope
Line 3
is a horizontal line and has a slope of zero
Line 4
slopes downwards from left to right and has a negative slope