Question 87824
Gn. x+4y=y. Therefore its parallel line is x+3y=some constant k
                                           x+3y = k
 Since it passes through (5,8) we have 5 + 21 = k
                                       => k = 26
 hence the required line is x + 3y = 26
                                3y = -x + 26
                                 y = -1/3x +26/3  of the form y =mx + c where m = -1/3 & c = 26/3