Question

Use the elimination method to solve the system of equations. Choose the

correct ordered pair.
7x+4y= 39
2x + 4y = 14
A. (3,2)
B. (5,1)
C. (5,4)
D. (3,4)

Answer 1

The answer is B.

Explanation:

When Elimination method is applied, you have to eliminate one of the variables from both equations. Firstly, both equations contain 4y so you can subtract it :

`7x + 4y = 39 - - - (1)`

`2x + 4y = 14 - - - (2)`

`(1) - (2)`

`7x + 4y - 2x - 4y = 39 - 14`

`5x = 25`

`x = 25 / 5`

`x = 5`

Next, you have to substitute x = 5 to any equations. I will choose to put in (2) :

`substitute \: x = 5 \: into \: (2)`

`2(5) + 4y = 14`

`10 + 4y = 14`

`4y = 14 - 10`

`4y = 4`

`y = 4 / 4`

`y = 1`

Therefore, put your answer in coordinate form :

`x = 5 \\ y = 1`

`(5,1)`