Question : The graph of the equation $x=a(a \neq 0)$ is a_____.

Option 1: line parallel to the x-axis

Option 2: line parallel to the y-axis

Option 3: line at an angle of 45 degree to y-axis

Option 4: line at an angle of 45 degree to x-axis

Question : What is the equation of the line whose y-intercept is 4 and is making an angle of 45° with the positive x-axis?

Option 1: $x+y=–4$

Option 2: $x–y=4$

Option 3: $x+y=4$

Option 4: $x–y= – 4$