Question

Solve the system by the elimination method.

3x - 2y - 7 = 0
5x + y - 3 = 0
To eliminate y, the LCM is 2. Which of the following is the resulting equations?

Answer 1

3x - 2y - 7 = 0

10x + 2y - 6 = 0

x=1 , y=-2

Explanation:

3x - 2y - 7 = 0

5x + y - 3 = 0

multiply by 2

10x +2y -6 =0

add the two equation together

3x - 2y - 7 = 0

10x + 2y - 6 = 0

---------------------------

13x +0y -13 = 0

add 13 to each side

13x -13 +13 = 0 +13

13x = 13

divide by 13

13x/13 =13/13

x=1

now to find y

5x + y - 3 = 0

5*1 +y -3 =0

5 +y -3 =0

combine like terms

2 +y =0

subtract 2 from each side

y = -2