solve the system of equations using the elimination method; x - 2y = 3 and x + 6y = 19

Question

Have have to get a answer for x and why 

Answer 1

To get x:

 

(1) x - 2y = 3

(2) x + 6y = 19

 

Multiply the first equation by 3.  The reason for this is then the value of y can be eliminated.

 

(1) 3x - 6y = 9

(2) x + 6y = 19

     ========

     4x + 0 = 28 (After adding the two equations together)

     x = 7

 

To get y:

(1) x - 2y = 3
(2) x + 6y = 19

Multiply the first equation by -1. The reason for this is then the value of x can be eliminated.

 

(1) -x + 2y = -3

(2) x + 6y = 19

     =========

      0 + 8y = 16 (After adding the two equations together)

     y = 2

 

The solution is x = 7 and y = 2