For a line to be parallel to x = 8, it has to start with x = some number. Such a line would have an undefined slope.
Now, x = y is a line that goes through the origin. It has a slope of 1. The answer to question #2 is y = 7
If a line is perpendicular to x = some number, then it has to be y = some number.
And this perpendicular line has to go through the point (4,7). So what is the y-value of this point, since the equation starts with y? The y-value is 7. So the equation has to be y = 7
