Question

the linear combination method is applied to a system of equations as shown.4(.25x .5y = 3.75) → x 2y = 15 (4x – 8y = 12) → x – 2y = 3 2x = 18what is the solution of the system of equations?(1,2)(3,9)(5,5)(9,3)

Answer 1

If we use the last equation:
2 x = 18
x = 18 : 2
x = 9
Then we will put it in another equation:
 x - 2 y = 3
 9 - 2 y = 3
 - 2 y = 3 - 9
 - 2 y = -6
  y = -9 : ( -3 ) 
  y = 3.
   The solution is : D ) ( 9, 3 )