Question

4x+y=15,3x+5y=41 solve by substitution and check the solution

Answer 1

Answer:

{x,y} = {2,7} 

Step-by-step explanation:

// Solve equation [1] for the variable  y 

 

[1] y = -4x + 15

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

  [2] 3x + 5•(-4x+15) = 41   [2] -17x = -34

// Solve equation [2] for the variable  x 

  [2] 17x = 34    [2] x = 2 

// By now we know this much :

  x = 2   y = -4x+15

// Use the  x  value to solve for  y 

  y = -4(2)+15 = 7