Question 55382
Please solve the system of linear equation by the addition method.
: 
x+2y=1
3x+4y=0
:
Choose a value to mult one of the equations, that will eliminate one of the variables when the equations are added together, here we can mult the 1st equation by -2; then we will have:
:
-2x - 4y = -2
 3x + 4y = 0
------------- add
  x + 0 = -2
      x = -2
:
Find the value of y using the 1st equation; substitute -2 for x
-2 + 2y = 1
     2y = 1 + 2
      y = 3/2
      y + +1.5
:
Check the two solutions by sustitution in the 2nd equation:
3(-2) + 4(1.5) = 0
  -6  + 6  = 0