Given:  Equation of the curve ……….(i)

  Slope of tangent =  …….(ii)

(a) Slope of the line  is 

 Slope of tangent parallel to this line is also = 2

 From eq. (ii),  

 From eq. (i),  

Therefore, point of contact is (2, 7).

 Equation of the tangent at (2, 7) is 

(b) Slope of the line  is  = 

 Slope of the required tangent perpendicular to this line = 

 From eq. (ii),  

 From eq. (i),  

=  = 

Therefore, point of contact is 

 Equation of the required tangent is