Answer: See explanation
Explanation:
From the question, we are told to prove that prove d + (8d + 1) + 7 is equivalent to 8 + 9d.
= d + (8d + 1) + 7
First we need to open the bracket. This will be:
= d + (8d + 1) + 7
= d + 8d + 1 + 7
Collect like terms
= 9d + 8
= 8 + 9d
Therefore, we have proven that + (8d + 1) + 7 is equivalent to 8 + 9d.