Find the equation of the x line parallel to the y-axis and drawn through the point of intersection of the lines x−7y+5=0 and 3x+y−7=0
The equation of any line through the point of intersection of the given lines is of the form
x−7y+5=0 + k 3x+y−7=0
⇒(1+3k)x+(k−7)y+(5−7k) = 0
If the line is parallel to y-axis then coefficient of y should be 0, i.e., k - 7 = 0, which gives k = 7.
Substituting k = 7 in (i), we get : 22x - 44 = 0 ∴x−2=0, which is the required equation.