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11 votes
11 votes
Brianna's teacher asks her if these two expressions 3x + 5 and 4x are equivalent.

Brianna says the expressions are equivalent because the value of each expression is 20 when x = 5.
Is Brianna correct? Explain your thinking.
Enter your response here

User Ian Overton
by
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2 Answers

10 votes
10 votes

Answer:

Yes, Brianna is correct because when you solve for x you get 5 and when you substitute you get 20.

Explanation:

combine like terms 4x-3x=x

5=x

substitute x with 5

3(5)+5=4(5)

distribute

15+5=20

User Meztihn
by
2.6k points
29 votes
29 votes

Answer:

No, because if x=? then itś, not a true equation, a true equation is when you have infinite solutions, in this case, if the problem is asking for 1 solution then yes, if it's asking for a true statement no.

User Brjv
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3.5k points