Question

Solve the system using substitution. Write the solution as an ordered pair. (1 point) SHOW YOUR WORK FOR FULL CREDIT! (2 points)

-5x + y = -1
y - 4x = -3

Answer 1

(-2, -11)

Explanation:

We are given the following two equations:

`-5x + y = -1` --- (1)

`y - 4x = -3` --- (2)

From equation (2):

`y=4x-3`

Substituting this value of y in equation (1) to get:

`-5x + y = -1`

`-5x + (4x-3) = -1`

`-5x+4x=-1+3`

`x=-2`

Now substituting the value of x in equation (2) to get:

`y - 4(-2) = -3`

`y+8=-3`

`y=-8-3`

`y=-11`

Therefore, the solution of the equations as an ordered pair is (-2, -11).

Answer 2

The solution is (-2,-11)

Explanation:

The given system is

`-5x+y=-1`

and

`y-4x=-3`

Make y the subject in the first equation to get;

`y=5x-1`

Put
`y=5x-1` into the second equation.

`5x-1-4x=-3`

Group similar terms;

`5x-4x=-3+1`

`x=-2`

Put
`x=-2` into
`y=5x-1`.

This implies that;

`y=5(-2)-1`

`y=-10-1`

`y=-11`

The solution is (-2,-11)