| 
 
 
| Question 78377:  I am not sure if this is solved by substitution, or elimination
 4x - 6y = -14
 x + 4y = 13
 Answer by dolly(163)
      (Show Source): 
You can put this solution on YOUR website! Solution by substitution: x + 4y = 13
 ==> x = 13 -4y ------------------(i)
 Plugging in this value of x in the first equation, we get,
 4(13-4y) - 6y = -14
 ==> 52 - 16y - 6y = -14
 ==> 52 - 22y = -14
 adding -52 to both sides,
 -22y = -14 -52
 ==> -22y = -66
 ==> -22y/22 = -66/22
 ==> y = 3
 Putting this value in (i), x = 13 -4(3)
 = 13 - 12
 = 1
 Thus x = 1 and y = 3
 Solution by elimination:
 4x - 6y = -14----------------------(1)
 x + 4y = 13 ----------------------(2)
 ==> 4x + 16y = 52 -----------(2) x 4
 4x - 6y = - 14 -------------(1)
 Subtracting the two equations we get,
 16y + 6y = 52 + 14
 ==> 22y = 66
 ==> 22y/22= 66/22
 ==> y = 3
 Plugging in this in (2), x = 13 - 4y
 = 13 - 4(3)
 = 13 - 12
 = 1
 Thus x = 1, y = 3
 
 | 
  
 | 
 |