Answers:
None of the five lines are horizontal or vertical
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Explanation:
Something like f(x) = 2x-5 is the same as y = 2x-5. This is because y = f(x).
Compare y = 2x-5 with y = mx+b. We see that m = 2 is the slope in this case.
The other four questions are handled the same way.
A horizontal line occurs when the slope is 0. Since none of the slopes are zero, none of the lines are horizontal.
A vertical line equation is of the form x = k, where k is any real number. The y variable is not involved. It is not possible to write a vertical line equation in the form y = mx+b because the slope m is undefined. So none of the given five equations are vertical lines.
Side note: something like y = x+6 is the same as y = 1x+6
