Question

3) Solve this system of linear equations by elimination.

y=x-1
2x-y=0

*x=-1,y=-2
*x=1,y=2
*x=2,y=1
*x=-2,y=-1

Answer 1

Solving this system of linear equations by elimination we get x=-1 and y=-2

Option 1 is correct option.

Explanation:

We are given equations:

`y=x-1---eq(1)\\2x-y=0---eq(2)`

We need to solve by Elimination method.

Elimination method: Add or subtract the equations to get an equation in one variable.

Rearranging the equation 1 we get

`-x+y=-1---eq(1)\\2x-y=0---eq(2)`

Add eq(1) and eq(2)

`-x+y=-1\\2x-y=0\\------\\x=-1`

So, after eliminating y we get x=-1

Now finding y by putting x in eq(1)

`y=x-1\\y=-1-1\\y=-2`

We get y=-2

So, solving this system of linear equations by elimination we get x=-1 and y=-2

Option 1 is correct option.