Question

2x+3y=7,-5x+4y=6 find X and y

Answer 1

// Solve equation [2] for the variable  x  
 

[2] 5x = 4y + 6 [2] x = 4y/5 + 6/5

// Plug this in for variable  x  in equation [1]

  [1] 2•(4y/5+6/5) - 3y = 5   [1] - 7y/5 = 13/5   [1] - 7y = 13

// Solve equation [1] for the variable  y  

  [1] 7y = - 13    [1] y = - 13/7 

// By now we know this much :

  x = 4y/5+6/5   y = -13/7

// Use the  y  value to solve for  x  

  x = (4/5)(-13/7)+6/5 = -2/7 Solution : {x,y} = {-2/7,-13/7}