Question

What is the value of the x variable in the solution to the following system of equations?

4x + 2y = 12
x − y = 3

A. 0
B. -3
C. 3
D. 2

Answer 1

The correct answer is C
`x=3`.

Step-by-step explanation

We have

`4x+2y=12---(1)`

and

`x-y=3---(2)`.

We solve the two equation simultaneously by elimination method. We need to be smart and eliminate y, since we are looking for
`x`.

We first multiply equation (2) by 2

`2x-2y=6---(3)`.

We add equation (3) and (1).

`\Rightarrow 6x=18`.

Dividing through by 6 gives

`x=3`.