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 = 18
What is the solution of the system of equations?

(1,2)
(3,9)
(5,5)
(9,3)

Answer 1

If you apply the linear combination method to the system like:
4(.25x + .5y = 3.75) → x + 2y = 15
(4x – 8y = 12) → x – 2y = 3
2x = 18
Then you can be sure that the solution of all this system is: (9,3). Hope this si what you were looking for

Answer 2

Option 4th is correct

The solution of the system of equations is, (9, 3)

Explanation:

Given the system of equations:

`4(0.25x+0.5y = 3.75)`

⇒
`x+2y= 15` .....[1]

`4x-8y = 12`

⇒
`x-2y = 3` .....[2]

Add equation [1] and [2] we have;

`2x = 18`

Divide both sides by 2 we have;

`x = 9`

Substitute x = 9 in [1] we have;

`9+2y = 15`

Subtract 9 from both sides we have;

2y = 6

Divide both sides by 2, we have;

y = 3

Therefore, the solution of the system of equations is, (9, 3)