Find the y-coordinate of the point of intersection of the lines

Question

 3 x + 4 y  =  1
− 4 x − 3 y  =  2

Answer 1

   3 x + 4 y  =  1 --------------> (1)

− 4 x − 3 y  =  2 --------------------> (2)

Multiply Eq (1) with 4 and Eq (2) with 3 and add both of them

Eq (1) X 4 ======>    12x + 16y  =  4

Eq (2) X 3 ======>  -12x  -   9y  =  6

                                   __________________

                                     0   +   7y   =  10

                                                 y  =  10/7

y co-ordinate of the point of intersection is 10/7.

Answer :

y co-ordinate of the point of intersection is 10/7.