Answer :
Brianna's thinking is incorrect.
Expessions A, and C. are equivalent.
For C, you add 5x and x together (because they have the same variable) to get 6x - 4.
For A, you subtract 9x and 3x (because they have the same variable) to get 6x- 4.
Expessions A, and C. are equivalent.
For C, you add 5x and x together (because they have the same variable) to get 6x - 4.
For A, you subtract 9x and 3x (because they have the same variable) to get 6x- 4.
Brianna's thinking is not correct. The equivalent expressions are expression A and C.
Which expressions are equivalent?
An expression is equivalent when they are simplified, they have the same value.
When expression A is simplified by adding 9x and 3x, the expression becomes 6x - 4. When expression B is simplified by adding 5x and x, the expression becomes 6x - 4. So, expression A and B are equivalent.
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