If 2x+y = 11, 2y+z = 12 and z+2x = 8, find the value of 2x + 3y +4z.
1) 29
2) 33
3) 25
4) 39

• 2x+y = 11 -->(1)
  2y+z = 12 -->(2)
  z+2x = 8 --> (3)
  
  from (3)
  z = 8-2x
  
  from (2)
  2y+8-2x=12
  y = x+2
  
  from (1)
  2x+(x+2) = 11
  3x = 9
  x = 3
  y = 5
  z = 2
  
  2x + 3y + 4z = 2(3) + 3(5) + 4(2) => 29
  
  Ans : 1) 29
• 10 years agoHelpfull: Yes(30) No(1)
• Z+2x=8
  =>z=8-2x,substitute z value in 2y+z=12
  =>-2x+2y=4 ,add 2x+y=11&-2x+2y=4 gives. Y=5
  Substitute y value in 2&3 equations gives x=3,z=2
  Therefore 2x+3y+4z=2(3)+3(5)+4(2)=29
• 10 years agoHelpfull: Yes(3) No(0)
• 29.solving these 3 eqn & putting the value of x, y,z in 2x+3y+4z we get 29.
• 10 years agoHelpfull: Yes(2) No(0)
• 2x+y=11------(1)
  2y+z=12-------(2)
  z+2x=8--------(3)
  
  
  2x+y=11*2
  z+2y=12
  
  4x+2y=22
  z+2y=12
  _________
  4x-z=10--------------(4)
  
  again ,solve eq(4)&(1) we get x=3
  now solving eq. 1 & 2 we get x=3,putting the value of x=3 in eq (1) we get the value of y=5,
  z=2.
  
  now by putting the value of x=3,y=5,z=2
  we get 29 as solution
  
  
  
• 10 years agoHelpfull: Yes(1) No(0)
• Ans : 29
  Without Finding x & y & z
  2x+y = 11 -->(1) 2y+z = 12 -->(2) z+2x = 8 ---> (3)
  
  (2)* 2=> 4y+2z=24-----(3)
  (3)* 2=> 2z+4x=16-----(4)
  (1)*-1=> -2x-y =-11-----(5)
  Add (3),(4) and (5)
  2x + 3y +4z=29
• 8 years agoHelpfull: Yes(1) No(0)
• 1) 29
  solving we get x=3, y=5 and z=2
• 10 years agoHelpfull: Yes(0) No(0)
• Ans 29
  X=3 y=5 z=2
• 10 years agoHelpfull: Yes(0) No(0)
• Solving the three linear equations simultaneously the answers for x=3,y=5 and z=2
  substituting these values to the given equations the answer is 29.
• 10 years agoHelpfull: Yes(0) No(0)
• opt 1) is the correct ans 2x=11-y; sub the value z-y+11=8; z-y=-3;
  2y+z=12 (-)z-y=-3 ; y=5;x=3;z=2;
  2(3)+3(5)+4(2)=29
  
• 10 years agoHelpfull: Yes(0) No(0)
• add three equ=>2x+y+2y+z+z+2x=31
  2(2x+z)+3y=31 put value from given equ 8
  3y=31-16 =>3y=15
  y=5,x=3,z=2
  2*3+3*5+4*2
  29
  
• 10 years agoHelpfull: Yes(0) No(0)
• 1) 29
  z-y=-3 & 2y+z=12 so y=5 and z=2 => x=3
• 7 years agoHelpfull: Yes(0) No(0)