how to solve algebraic equation using elimination method

how to solve algebraic equation using elimination method

Tutors, sign in to answer this question.

x + y = 8 eq. 1

2x = y - 5 eq. 2

move variables around fo eq. 2 so it will have same form as eq. 1:

2x - y = -5 eq. 3

add eq. 1 to eq. 3:

x + y = 8

2x - y = -5

3x = 3

x = 1

lets use eq. 1 to figure out y value by substituting value of x:

1 + y = 8

y = 8 - 1

y = 7

therefore** x = 1, y = 7**

The first equation has x and y on the left with a constant on the right. Let's change the second equation to match that format:

2x = y-5

-y -y

2x - y = -5

Now, we can take our original first equation and add it to the new format of the second:

x + y = 8

2x - y = -5

Notice that the y and the -y cancel each other out, leaving us with only x as a variable.

(x+2x) + (y-y) = 8+(-5)

3x = 3

Divide both sides by 3:

x = 1

Now, substitute 1 in for x in either of the original equations. Let's use the first one, since it is a little simpler than the other:

x+y = 8

1+y = 8

-1 -1

y = 7

So, the final answer is x=1, y=7.

Already have an account? Log in

By signing up, I agree to Wyzant’s terms of use and privacy policy.

Or

To present the tutors that are the best fit for you, we’ll need your ZIP code.

Your Facebook email address is associated with a Wyzant tutor account. Please use a different email address to create a new student account.

Good news! It looks like you already have an account registered with the email address **you provided**.

It looks like this is your first time here. Welcome!

To present the tutors that are the best fit for you, we’ll need your ZIP code.

Please try again, our system had a problem processing your request.