Question

Solve the system by substitution.
−9y-2=x
4x-3y=31

Answer 1

Answer:

System of Linear Equations entered : [1] -9y-2=x [2] 4x-3y=31 Equations Simplified or Rearranged :  [1] -9y - x = 2   [2] -3y + 4x = 31 Graphic Representation of the Equations

Solve by Substitution :

// Solve equation [1] for the variable  x 

 

[1] x = -9y - 2

// Plug this in for variable  x  in equation [2]

  [2] -3y + 4•(-9y-2) = 31   [2] -39y = 39

// Solve equation [2] for the variable  y 

  [2] 39y = - 39    [2] y = - 1 

// By now we know this much :

  y = -1   x = -9y-2

// Use the  y  value to solve for  x 

  x = -9(-1)-2 = 7 

.: {y,x} = {-1,7}