Question

4x+2y=8 3x-y=-1 by elemination method​

Answer 1

Answer:

Since we have the equations starting with 4x and -4x, it looks like we can combine them straight off and eliminate x:

-4x + 2y = 8

4x - 3y = -10

-y = -2 ====> y = 2

Plugging into either equation,

-4x + 2(2) = 8 ===> -4x + 4 = 8 ===> -4x = 4

x = -1

So our solution is (-1, 2)

Answer 2

Answer:

Solve equation [2] for the variable  y 

 

[2] y = 3x + 1

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

  [1] 4x + 2•(3x+1) = 8   [1] 10x = 6

// Solve equation [1] for the variable  x 

  [1] 10x = 6    [1] x = 3/5 

// By now we know this much :

  x = 3/5   y = 3x+1

// Use the  x  value to solve for  y 

  y = 3(3/5)+1 = 14/5 

Solution :

 {x,y} = {3/5,14/5}