Solve the following pair of linear equations by the elimination method and the substitution method
3x – 5y – 4 = 0 and 9x = 2y + 7

3x - 5y = 4    ...(i)
9x - 2y = 7    ...(ii)
For making the coefficient of x in (i) and (ii) equal, we multiply eqn. (i) by 3 and subtracting, we get
   9x - 15y = 12
   9x - 2y = 7
  -    +        -
-13y    = 5

Now putting the value of y in (i), we get

Substitution method :
We have,
3x - 5y = 4    ...(i)
9x - 2y = 7    ...(ii)
From (i), we have
3x - 5y = 4

Substituting the value of (iii) in (ii), we get

Now, substituting the value ofy in (iii), we get