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Answer:

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Given:

Find:

Solution: The first step that we need to take to simplifying the expression is to distribute the -7 value to the values inside of the parentheses.
After doing the distribution, now we can combine like terms. Combine like terms means that we combine values that are similar to each other. For example, we have -28x and 7x which both have the x variable attached to a number. Therefore, we can combine those values to produce -21x.
Therefore, the final answer would be -21x + 14.