For this case we have the following expression:

Applying distributive property to the terms within parentheses taking into account that:

We have:

We add similar terms taking into account that:
Equal signs are added and the same sign is placed.

Thus, an equivalent expression is:

Answer:

She reached 6 miles on her 30th day.
Equivalent expressions are expressions with the same value.
The equivalent expression of
is 
Given that:

Open brackets

Collect like terms


Hence, the equivalent of
is 
Read more about equivalent expressions at:
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