x + 109 = x + 89

- x - x

109 = 89 , but 109 ≠ 89

I don't understand how to do the question.

Tutors, sign in to answer this question.

x + 109 = x + 89

- x - x

109 = 89 , but 109 ≠ 89

Michael F. | Mathematics TutorMathematics Tutor

Without any algebra, it is not possible for 109 added to a number to be the same as 89 added to the same number.

If you need a proof, I will show that if a+b=a+c then b=c

b=b+0 definition of 0

=b+(a+(-a)) every number has an additive inverse

=(b+a) +(-a) associative law of addition

=(a+b) +(-a) addition is commutative

=(a+c) +(-a) by hypothesis

=(c+a) +(-a) addition is commutative

= c+(a+(-a)) associative law of addition

=c+0 definition of additive inverse

=c since 0 is neutral element for addition

Hi Haylie;

x+109=x+89

Is it possible that this is...

x+109=3x+89

?????

I will resolve...

x+109=3x+89

Let's subtract x from both sides...

-x+x+109=3x+89-x

109=2x+89

Let's subtract 89 from both sides...

-89+109=2x+89-89

20=2x

Let's divide both sides by 2...

20/2=(2x)/2

10=x

Let's check our work...

x+109=3x+89

10+109=[(3)(10)]+89

119=30+89

119=119

David M. | Math Tutor in Many Areas.Math Tutor in Many Areas.

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.