Jessica rewrites Expression 1 as d + d + d + 5 + 5 + 5.
Why might she have done this?
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Answer:
she wrote it to make it simpler to add.
Step by step:
A triangle has 3 sides. It's given sides are d+5. All sides are d+5 because it is an equilateral triangle.
The answer to the question you were looking for is: SHE COMBINED THE LIKE TERMS SO IT WOULD BE EASY TO ADD THEM.
Hope it helps....