Q1. X = 8 is just a straight vertical line, so the only other straight vertical line here is x = 7, which is the answer.
Q2. This is another straight vertical line. To find a line perpendicular to it, we just need to find one that's "y = ___" We know it's going to be A or B. Because it's asking for a line that passes through (2, 6), we know that y = 6 is the only correct choice.
Q3. This is yet another straight horizontal line. We know the y value of whatever our coordinate pair is is going to be 8. Because only option D has a y value of 8 in both coordinate pairs, it is the correct answer.
Q4. The line is horizontal, because it's stating that the y value of the line will always be the same. Because this is a horizontal line, the slope is equal to 0.
Q5. The line that is perpendicular to the vertical line and passes through the coordinate pair is y = -2.